O.C. POP MUSIC REVIEW : Down Home With Doc : Flatpicking pioneer Doc Watson brought a mood of front-porch fellowship to an audience of strangers Sunday at the Coach House.

Besides the fact that Orange County guitarist Dan Crary, a splendid flatpicker, was an ideal opening act for Doc Watson at the Coach House on Sunday, Crary’s presence was also a handy thing for any music critics in the audience. Crary, a Cal State Fullerton speech professor by day, neatly summed up the profound influence that Watson (and his late guitar-picking son and partner Merle) had on music: “They’re the ones who made the flatpicked guitar legitimate and magnificent around the world.”

Watson, 67, has always been a national treasure, and his impending retirement only served Sunday to highlight what a rare and marvelous thing a Watson performance is.

Amid his 20-song show, there were still sparks of the fret-board fire that has inspired three decades of guitarists. But he mostly kept the heat in the oven, providing a warm accompaniment to his songs.

If Watson didn’t play guitar--indeed, if he didn’t even sing--he would likely still have drawn adoring audiences.

The blind, Deep Gap, N.C., native embodies an endangered American spirit: Whether he’s singing the deep blues or spinning the corniest yarn, one gets the feeling that Watson is sharing all he has, bringing a mood of front-porch fellowship to an audience of strangers.

To have that basic magic coupled with a spell-weaving guitar technique and evocative baritone voice makes for one truly great communicator, and Watson was in fine form Sunday. With a more-than-able assist from his accompanying guitarist, Jack Lawrence, he conjured an autumn forest-full of moods.

Watson effortlessly ranged from Tom Paxton’s early-’60s “Wonder Where I’m Bound” drifter’s lament to a lively, peppery vocal on “You Don’t Know My Mind Blues,” by the obscure Southern blues man Bar-B-Q Bob.

From the Delmore Brothers country catalogue, he played the good-naturedly apocalyptic “Deep River Blues,” which included the line “My gal, she’s a sweet ol’ gal / Walks just like a waterfowl.” Watson and Lawrence moved some lovely, sad harmonies through Flatt and Scruggs’ “Corrie Is Gone.”

They offered two Jimmie Rodgers tunes--”One that has yodeling and one that ain’t,” Watson detailed.

For the one with, Rodgers’ 1927 “Sleep, Baby, Sleep,” Watson warned the club’s sound man, “If you’re near your meters, you’d better get your head back when I start yodeling: One of them might fly off and hit you.” He did indeed deliver some keening yodels, along with a lyrical guitar solo.

Lawrence, a fine flatpicker who melds Watson’s style with touches of Django Reinhardt, flew on his own instrumental “Ten Miles to Deep Gap” as well as in the frequent solo nods Watson gave him.

An instrumental romp through “Sweet Georgia Brown” was one of the few occasions where Watson matched Lawrence’s speedy elegance with some flash of his own, while on “Florida Blues” the pair indulged in some lightning-fast harmony lines.

Then came a veritable thunderstorm as Crary (who was reviewed recently) joined them for wild picking flurries on the final three songs and an encore of Bill Monroe instrumental tunes.

Watson hasn’t yet set a date on when he’s retiring. But should he come around again, be sure to see him, because he’s going to be a long time gone.