Bad form on the part of the do-er doesn't really bother me as much as it used to. I think that if people want to waste their time that's their business so as long as they are considerate enough to do their sets in bad form and clear a machine, etc then it's all good. One thing no one likes is a know it all so as tempting as it is to point out a few flaws for me it's just best to try and ignore that and focus on my own work.
The pet peeve that gets me is the person who comes over and hovers over me in the middle of a set just to let me know that they want to work in. I'm totally fine sharing just don't get up in my grill when I'm trying to maintain focus on good form!!
I'll see you and certainly let you in but sheeeeesh ... back off a bit!