Polo Rules

The difference of the effect between hacking and hooking is clear to see in that initiating hackers often (imho) want to be seen as more competitive/aggressive/'committed' players as part of their weaponry and they are liable to get more 'aroused' in hacking duels they've instigated. There's a second form of hacker - usually the ball carrier pre-empting interference by hacking blindly and then carrying on their run. The effect is the same - the hack nearly always seduces or demands a response as it is often (mis?)read as a personal attack on a player and as such can quickly escalate and threaten to dominate a game. Serial hackers however draw attention to themselves and probably have referees attentions on them (rightly or wrongly) in anticipation/indication of more serious fouls or aggravation during the match... Not sure what the penalty is this year but referees need to penalise the first instance in every game to ensure that hacking doesn't escalate and lead to other misdemeanours.

The hook is a (momentarily) more considered, calmer and therefore more skilful move in both execution and deed. In close quarters there is no such duelling with hooking - it's usually from behind the player being hooked and rarely has that immediate hack-back response (however aggrieved the person too slow to get that shot/pass away might be!), therefore rarely escalates or infect the mood of the whole game - therefore I think worthy of being retained.