A curious and challenging thing "feedback" can be. We ask for feedback, but often cringe when it's given. I say "we" because I've done the same. I often wonder why that is. Certainly, in the case where no feedback was asked for, it likely wouldn't be well received. Perhaps when we ask for it, we're really hoping to hear "Doing great!", "Wow, you're incredible!", "I'm really impressed!", or "Keep up the great work!". But when we hear feedback like, "Um... you know... you should really work on your touch. You're banging on the keys" (Hal Galper, to me, at Aebersold clinic), "Man, that note is really sharp!", or "Don't give up your day gig!", it's a little harder to swallow. While that last one is just a joke, constructive and appropriate criticism is often as difficult to give as it is to take.
For the most part, unless we're in a "teaching/learning" scenario (like an Aebersold clinic), the most benefit will be gained by carefully and actively listening to each other. In particular, listen to the stronger members of the group. This type of communication gets better as we get better at listening and at articulating our musical intentions through our instruments. In fact, if I can't demonstrate something on my instrument, I avoid trying to talk too much about it. Even when I can demonstrate a concept on my instrument, I often come up short when tying to use words to describe the concept. One of the beautiful characteristics of music is that words often fail to capture it's essence.
All that said, it seems important that we carefully choose our words, and that we're very specific when offering feedback. In addition, feedback sought after should be received graciously, and "seasoned with a grain of salt".