I have to say I have come across quite a lot of the aforementioned behaviour with juniors. I don’t know if it’s something coaches are telling them to do or it is something which comes naturally to em, but I’ve dealt with everything from knuckle cracking, annoying noises, clock bashing, piece screwing, loud burping, going for a confab with his dad in the middle of the game while his dad fiddles with Fritz on the laptop (!) and most annoying of all repeated draw offers (sometimes twice in the same move!). I also once had a kid who was playing on with a loan king and 2 pawns against my Q and about 5 pawns, repeatedly announce stalemate (it wasn’t he had pawn moves) at the top of his voice
I had a particularly miserable British a few years back in Coventry because I had a junior in pretty much every round, they came with all the aforementioned behaviour but also seemed to be of a better class player than you usually come across
- I felt like kinder garden cop in that tournament!