I wrote in part two of this three-part series on American steaks ["Aging with Grace (and Science)," August 30] that steak houses don't serve USDA Prime filet because the cut is too tender. That remark provoked some mail. As it turns out, there are a few steak houses that serve USDA Prime filet mignon. And tasting one of these steaks provides me with a surprising insight into the relationship between marbling and meat quality.

I am dining with a rare bird, a Nebraska native who is not very fond of beef. "I guess I ate too many tough-as-leather steaks when I was a kid," he shrugs. My friend orders the well-marbled filet, and I get the T-bone, which was not featured on the platter. We also order a bottle of Gigondas from a very well put together wine list. The wine cellar here holds 15,000 bottles, and the list is the size of a phone book.

Like Greenbriar Chophouse, Lynn's Steakhouse is located in an office park. But here they have transformed the industrial space into something that feels like a French country inn. Grapevines and tiny white Christmas lights are strung from the walnut-stained rafters, and much of the wall space is covered with wine racks. Like all such manufactured atmospheres, it has a theme-park phoniness about it, but it's still a lot more pleasant than the faux Denny's decor at Greenbriar.

When our steaks come to the table, the waiter pulls out a flashlight and asks us to check them for doneness. We have both ordered medium rare. My friend's filet is raw in the middle, and my T-bone is overcooked, so we send them both back. The T-bone is a much thinner cut than I expected, maybe three-quarters of an inch. No wonder it wasn't on the platter with the two-inch-thick strips, the big round filets and the other recommended cuts, I think, as I give myself a mental smack on the forehead.

The side dishes at Lynn's include my two steak-house favorites, creamed spinach and crispy potatoes, both served family-style and both excellent. The crust on the sourdough is a little too soft, but we didn't come here for the bread. My friend's filet required only a few more minutes under the broiler, so the University of Nebraska grad kindly splits it with me while they start over on my T-bone. (I take back everything I ever said about Cornhuskers.)

Having spent his childhood chewing his beef until his jaws ached, my friend is ecstatic about the texture of the filet. While the filet cuts effortlessly and practically melts in your mouth, it is not my kind of steak. To my taste, this kind of mushy meat has all the appeal of steak-flavored mashed potatoes. But the quishy steak does bring up several interesting questions about highly marbled meat.

When the USDA grades beef, it is basically measuring marbling, or intramuscular fat. The fat melts and bastes the meat as it cooks, providing more flavor and tenderness. Ever since 1987, when the USDA reprioritized its grading system and the American cattle industry began feeding cattle differently in order to produce leaner beef, gourmets and steak lovers have been screaming in protest. By 1995 USDA Prime accounted for a mere 1.3 percent of fed beef.

Noting that USDA grading standards have been revised downward continuously since 1928, Jeff Steingarten of Vogue writes, "I have heard old-timers say that the fabled marbling of Japan's costly Kobe beef today looks just like a USDA Prime steak did 50 years ago. The downgrading of American meat is a major scandal, a venal conspiracy…"

No doubt the USDA's standards have changed. But would a steak with "the fabled marbling of Japan's Kobe beef" actually be the ultimate in quality?

The black steer has a strange look about it. It's smaller than most beef cattle, and its ass end seems to be higher in the air than its shoulders. "That one is about seven-eighths Wagyu," rancher Don Lively tells me as we drive around his Georgetown spread in a pickup truck. Wagyu cattle are the source of Kobe beef. The Japanese have long classified the genetics of the breed as a national treasure, thereby preventing any export of cattle or semen.

In a madcap escapade, the details of which have never fully been disclosed, four Wagyu bulls were smuggled out of Japan aboard a jetliner bound for the United States in 1976. They eventually found their way to this Georgetown ranch, where they became the foundation of the North America Wagyu herds. In taste tests, beef from the American Wagyu cattle couldn't be differentiated from the Japanese variety. With Japanese Kobe beef selling for $128 a pound, the prospects of an American Wagyu herd electrified the cattle business. In 1991 The Wall Street Journal reported that the bull semen in Lively's storage shed was worth more than $2 million.

Today, American Kobe beef has become available to restaurants and consumers who care to order it. It goes off the top of the charts in terms of USDA grading. It is more highly marbled than anything produced in this country for decades. And most American steak lovers couldn't care less.

"The Wagyu thing never really amounted to much," says Lively, who has more or less retired from the business. "There's a little specialty market for American Kobe, but that's about it." At www.farm-2-market.com, eight 12-ounce American Kobe filet mignon steaks are selling for $248, or about $41.33 a pound plus shipping and handling, roughly a third of the price paid in Japan.

If that sounds like a lot of money, consider that Lively once sold female Wagyu cattle for $25,000 to $30,000 apiece. (An average Black Angus cow fetches around $800.) With that kind of investment on the line, cattlemen need big returns. And the American market isn't providing them. Even if you do sell American Kobe steaks for top dollar, there is little interest in the rest of the steer. "Prime cuts make up only about 20 percent of the meat," Lively notes. "What do you do with the other 80 percent? It makes great hamburger meat -- if you want to pay $100 for a hamburger."

Dr. David Lunt, who worked on Wagyu breeding experiments at Texas A&M's McGregor Research Center, told the campus newspaper, The Battalion, in 1991 that the meat might be sold in Japan but would never catch on here because it had too many calories. The USDA Choice that most of us prefer for our filet mignons contains an average of approximately 8 percent fat. USDA Prime is roughly one-third higher in marbling, or around 11 percent fat. The American Kobe produced at Texas A&M in 1991 tested at 22 percent fat, double the content of USDA Prime. A 12-ounce steak of American Kobe beef contains 674 calories from fat alone.

Many food writers, myself included, have clamored for a return to the good old days of highly marbled beef. But the reality is that highly marbled beef is already available and few of us really want to eat it. Kobe beef is eaten in little sushi-sized chunks in Japan. But Americans, and particularly Texans, aren't going to start eating such dainty portions anytime soon. And when it comes to a nice big steak, 22 percent fat is just too much of a good thing.

The waiter finally arrives with my T-bone. It's perfectly cooked, and I offer to split it with my dining companion. After an experimental bite, he decides to pass. Half of the 12-ounce filet was plenty of meat for him, and besides, he finds the broad side of the T-bone "too chewy." The tenderloin side tastes a lot like his butter-soft filet, only thinner.

Personally, I like the "chewy" side better. This is the top loin, which is also sold as New York strip. This cut is often described as more flavorful than the filet, but I wonder how much of this has to do with its firmer texture. Maybe all our lobbying for more marbling and higher USDA grades has been misguided. I have to admit that there is something satisfying about a steak that puts up at least a little bit of a fight.

On reflection, this insight makes sense. I remember one of the best filets I ever had was in Argentina. Grass grows year-round there, and the cattle are not grain-fed. As a result, much of the meat is too tough for American tastes. I could barely chew the sirloin. But the lomo, as the tenderloin is known, offered a wonderful combination of rich flavor and not-too-tender texture.

And on the basis of my reaction to the USDA Prime filet at Lynn's Steakhouse, I doubt that I'd find much to love about American Kobe beef, or the highly marbled USDA Prime of the 1920s that it is said to resemble.

Dr. Dan Hale at the Texas A&M Meat Science Center has said that higher USDA grades are not the point. He's right. The point is quality.

Tenderness, juiciness and flavor may be the three key palatability factors in defining meat quality, but I think the scientists are overemphasizing tenderness. And at some point the pursuit of tenderness runs into the wall of mushiness. What satisfies me in a steak is an elusive balance of tenderness, juiciness and flavor. Besides, I don't believe meat scientists will ever quite find a way to objectively define beef quality. My tastes and those of my dining companion are as contradictory as the tastes of the Argentines and the Japanese.

But if American steak once suffered a decline, it can now be said to be on the upswing. According to the 2000 National Beef Quality Audit, USDA Prime production has more than doubled in the last five years. And as scientists have come to better understand what makes meat taste good, the American steak also has improved by measures that transcend USDA grading. The options for cattlemen will continue to expand. Genetic analysis will soon pinpoint the genes that control flavor and tenderness. Chemical injections, electrical stimulation and other technologies will give meat packers more control of the aging process.

The brand names in your grocery store meat case, like Certified Angus, Nolan Ryan Tender Beef and Sterling Silver, are just the beginning. The American cattle industry has entered an era of niche marketing. Cattlemen one day will choose to produce lean beef, marbled beef, American Kobe and every other taste under the sun. And American steak houses will offer menus to match.

As for finding the steak of your dreams at Lynn's Steakhouse, I'd recommend that you skip the skinny T-bone and order the filet only if you like your meat extremely tender. Now that I know my way around their meat locker, I am going to try the thick-cut, dry-aged USDA Prime New York strip next time. I'm guessing it will come much closer to the ideal combination of marbling, aging and texture. Maybe next time I'll find that perfect balance between flavor and tenderness.

Maybe next time I'll eat the great American steak.