Audiences only really like two parts of a show — the beginning and the end. You should prolong the former by rolling directly through your first three numbers without pausing. Then make sure you end suddenly and unexpectedly. Audiences rewards who stop early and punish those who stay late…
Finally, there’s nothing an audience enjoys more than hearing something familiar. If you think your songwriting and all-round musical excellence are enough to entertain a bunch of strangers for an hour with songs they have never heard before, bully for you. The Beatles didn’t, but what the hell do they know?
That is from the entertaining and insightful David Hepworth book Nothing is Real: The Beatles Were Underrated and Other Sweeping Statements About Pop. He lists the following as the ten best blues songs ever:
Memphis Jug Band: K.C. Moan
B.B. King: You Upset me Baby
Blind Willie Johnson: Dark Was the Night
Mississippi Fred McDowell: Shake ‘Em On Down
Lightnin’ Slim: Rooster Blues
Muddy Waters: Too Young to Know
Elmore James: I Can’t Hold Out
Otis Rush: All Your Love
Richard ‘Rabbit’ Brown: James Alley Blues
Blind Blake: Too Tight
By the way, Paul and the Beatles really did record both “I’m Down” and “Yesterday” in the same day.