Jam Safe - Playing with Others Series

What's a jam-safe song? In short it's a song that uses a groove and form that we've heard and played many times before. For grooves this is commonly: shuffle, swing, slow blues, rhumba, two-beat (Mojo and lazy) and rock beat. As for the form, it really means one, the 12 bar blues.
 
If you and they band are accomplished, then you can experiment with 16 bar blues (commonly doubling the opening four measures of the I Chord), 8 bar blues ("Key to the Highway" is the most common progression: I V IV IV I V I V), modal blues (no chord change) and alterations to the 12 bar blues (such as "Stormy Monday" changes [i7 ii7 iii7 flat-iii7 in measures 7 and 8], I VI II V turnarounds, ii7 V7 I7 replacement for measures 9 and 10 and bridges [commonly 8 bar: IV I IV I IV I ii7 V7]). If you call something other than a 12 bar, then be prepared to speak in detail of how the chord changes go and also keep in mind that you may need to abandon ship if the band looks like they're not confident with it... choose another song that's a 12 bar ;-)