Well, in fact there are some Southern Hemisphere players in the Winter tournament and a lot of Northern players in the Southern Tournament.
And to be honest I just went there to look up if I was in the correct one, which happened to be the case, since I wasn't sure that I did realize it was a regionally divided tournament.
Either there is a way to ensure people playing under their correct flag (I could sign on for Kenia or something, who would know different?) and exclude people OR the titles should be treated as suggestions.
There are only 64 slots in the Northern Hemisphere 1200-1399 which seems very few to me, since it is the strongest band in terms of numbers of players, and it IS tempting to snatch one of the other 64 slots of the 'wrong' hemisphere.
PLUS: People are normally ignorant of these haggles. I remember asking a 1500+ player who happend to have suffered a dip to retreat from a 1200-1299 tournament and got the reply: this is the one I may enter, and I need to get back to my rating. Can I do anything. No, and in one viewpoint he is even correct.