Boz Scaggs & Michael McDonald Verizon Wireless Theater October 1, 2011

Now, Classic Rock Bob doesn't want to come off as some sort of out-of-touch curmudgeon ("What do you mean you don't sell cassettes anymore? Hey! You kids get off my lawn!"), but one of the reasons to love classic rock is very simple: Much of it is performed by real, living, breathing musicians who have spent years - and in many cases, decades - honing their songwriting skills and playing on real instruments.

So it was a pleasure to see a Master Class in the subtler side of classic rock, with side trips into balladry, blues, R&B, gospel, and even zydeco, with Saturday's double-header featuring almost three hours of incredible music.

Opening the Houston date was Scaggs (above), for whom the word "tasteful" is tailor-made. His distinctive vocal tone - still hitting the high falsettos at age 67 - and compact, never extraneous guitar playing were on full display, along with a personable playfulness absent from his Stafford Centre gig this past February.

That the set list contained exactly half of the tracks on his best known record, 1976's Silk Degrees, plus the disco-tinged hit "JoJo" and Urban Cowboy soundtrack ballad "Look What You've Done to Me" showed that he wanted to stick to more audience-familiar material, with "Harbor Lights" a particular standout.

But he did pull out the lush & sexy "Desire" from his last all-original studio release, Dig. "Here's an album that we put out, but it got kind of lost because of other, more important events," Scaggs said. Left unsaid was the work's release date - September 11, 2001.

Nestled on a seat behind his electric piano, Michael McDonald combined the big hits from his years with the Doobie Brothers, solo material, and classic songs from his three records of Motown covers. And that distinctive, sexual bear voice of his brought forth actual squeals from some women in the audience.

However, an MOR ish, ballad-heavy middle portion of his set halted an early momentum built with "It Keeps You Runnin'" and "I Keep Forgettin'" before things picked up again. Of the Motown material, his take on the overplayed "I Heard it Through the Grapevine," was still nothing short of revelatory.