I think it's very situational. Personally I won't do a T16 foul unless there is banter between the coaches that invites it, or occasionally as way to let off steam after a particularly bad game! In a league situation where a rival leaves an important player open to a foul may be another situation where I would consider it. In the OCC there are awards for players that foul a lot, so T16 fouling is often encouraged! In terms of my opponents doing it me I feel that it is part of the game and within their rights to do it to me. From a fluff perspective it makes no sense that two teams that spent all match trying to kill each other suddenly stop doing it because it's turn 16. Of course the lame part is that there is no risk in doing it in T16 and often no tangible reward in the current game either. My rule of thumb is that if it's allowed by the rules then there is little point in complaining about it, unless you think the rules are wrong and you can get it changed somehow!