should implement the rule like that one eu tourney did where you have 10 seconds to attack and if you don't you lose the round so you don't have people s keying away
^ this
For one, it's an attacking rule, not a proximity rule. Doesn't do anything against s keying.
Two, you could just use smaller arena's to limit s keying and ensure combatants are engaging.
But three, it slants the tournament to accommodate some play style's and punish others. If people aren't able to play as they want, then they aren't playing at their best, and winning a tournament off the back of a rule set is weak.