In my original post, I was talking about songs which you'd never heard before . . . not a clue as to how it goes . . .
I'm not talking about the standard songs with 3 - 4 chords . . .
I can almost always figure out the chords of a song by listening to it.
What I was getting at in my original post was that figuring out the chords in a song as it plays - sounds like you don't know the song, and are just learning it.
When the chorus comes around, someone always would hit the wrong chord, until they figured out the chorus.
And if you're watching the guy next to you, to see what he's playing - he may be guessing, too, and screw you up.
So - the song would basically sound real amateurish, until everyone figures out the patterns.
Everyone's always got it by the time the song is ending . . .
But - by then it's too late. And, the guys who just figured it out, - heck - they want to keep playing it, now that they know it . . .
Some of you may jam with songs that have 4 - 6 chords, but when it's a song you've never heard, with a dozen chords, and 2 - 3 different rhythms, and it's got a different intro, the verses, chorus, and 2 different bridges, not to mention a different ending - it can sound like crap if you only have 1 or 2 guys who know the song, and 6 who don't.
Lead players probably have it easier than rhythm players. They have a better chance of grabbing a right note. 5 - 6 notes to choose from, with every chord.
But sometimes a D7 might be interpreted as a D, or a D add F, or Dm, or D9, or BM, or a Bm7 or . . . .
It's fun playing in a jam band, don't get me wrong. And every so often, it sounds great. And there's a lot of smiles and all, and you make new contacts . . .
So - overall, it's a good time.
I prefer playing songs where everyone is always playing the same song, but it's fun, and it has it's moments . . .