Just depends. Long, multipitch routes - just two. Cragging at the red - 3-6 (as long as everyone is motavated and team players). Bouldering sessions - 1-12, as I have had great times by myself and with a dozen+ people. Overall, though around 4 seems to be pretty good. That way you have some extra hands around to take pics or swich out belaying duties.
I used to think, "The more the merrier," but now I realize how annoying it is to be in a large group (maybe because I actually climb now). Even in a group though, I try to stick to one person.
diggum i hear you!!! (intended) I'm partially deaf myself...so hearing is already hard enough....
bouldering...lots
sport...if everyone's quiet and spaced out I like up to 10...but if there are lots of girls along it tends to get loud...so maybe 4-5...
in RQ....omg if there's a group of kids in there!!!
It's best to come with a small group so that you can split up since not everyone wants to climb the same thing. However, its good to show to the crag and know most of the people their, even if only by casual aquintance.
I like to climb in groups of 2... 2, 4, 6... with a rope for every pair that way if anyone gets bored they can jump on something...
I know they sell the silent-partner and soloist... but I"ve never heard of anyone going out and climbing on their own on a regular basis... Does anyone do that?