Safety is usually the one thing that gets under my skin. I got a 1 game suspension a few years back from yelling (not swearing) at a ref because the same player on the opposing team kept slide tackling and our rec league bans it. By the third blatant tackle, I lost it as I had one kid knocked out of the game as he took studs to the ankle that drew blood (probable Red at any level) and several other kids looks like they were about to brawl. The ref responded by saying in his judgement that it wasn't a slide tackle and the other coach said that slide tackling was allowed. I got berated by the Commissioner after but, I did point out that 1) the other coach either lied about slide tackling or did not read the rules, which was a requirement, because I was the one responsible for editing the rule book that season. I also noted that I had to do something during the game about slide tackling because of immediate player safety concerns while, on the other hand, I said nothing during the game when the opposing kepper made a save in the field of play, rolled with the ball in his hands 3 times over the end-line, and the Ref gave them a goal kick. That was in my game report instead.