I also think 'tired' gets mixed up with coaching strategy. Geno with a sizable lead goes to a 'use 25 seconds of clock' offensive system in a lot of games and while it limits the fourth quarter offensive sets for the opponent and insures a win, can also lead to a lower energy feel to Uconn's play - they typically stand for the first 10-15 seconds of half court offense before cranking it into gear again - something that isn't all that easy on the players. Those ten seconds standing and watching a player dribble near mid-court allows the players to actually feel the bumps and bruises sustained during the first 30 minutes and they may notice some muscle fatigue as well. So they too may actually begin feeling a little tired when if they were running offense at their usual pace, they wouldn't notice at all.
I do think tired can come into the equation - they played 11 games in 37 days with what were I am sure hard practice on most non-game days. Throw in exams and being challenged every day by a hard driving coaching staff and an impressively tough OOC and a few days home with friends and family and no basketball will be a welcome chance to completely relax. In years past we always expected a team malaise striking early in February for the same reason - the season can seem awfully long during the second 'half' after Christmas - call it tired or complacent, or doldrums, or whatever - it does seem to be real, and Geno himself used the 'tired' qualifier in I think the last two press conferences - time for a little recharge.