SPs are falling once rotation POSSIBLY a set earlier b/c i see no really way they could beat a good enboar/reshiram list or for that matter most of the stuff in BW that is fast or playable.
And hey if rotation is the only thing that kills this monster i'd say it was the best reign ever for a deck, better than delta, better than plox etc.
I mean the bdifs for each format are listed
PL: Dialga Lock, Palkia Lock, Dialga/Palkia, GeChamp
RR: LuxApe, FlyChamp, LuxBox, Mother Gengar
SV: DialgaChomp, LuxChomp, Blazeray, FlyChamp
PA: DialgaChomp, LuxChomp, Blazeray, CurseGar
HGSS: Gyarados, LuxChomp, Jumpluff, CurseGar, DialgaChomp
UL: Gyarados, LuxChomp, Jumpluff, CurseGar, Sablelock
UD: LuxChomp, VileGar, Sablelock
TU: LuxChomp, VileGar, Gyarados, Sablelock, Magnezone
COL: LuxChomp, LostGar, Sablelock, Magnezone
Pretty dominant, hey some liked it some didn't but you can't argue that w/ SP coming out the "tech" became more important than ever and SP deckbuilding became quite literally a science(also decks aren't in any particular order)