Regarding the third periods last year, can't see that it was a matter of conditioning. Backing in and parking in front of your own net while opponents get free shots through the screen you've created, uses little energy, but who knows if it's a sign of being worn out. I'd guess it was more a matter of being afraid to lose a lead.
The Sioux of 2001 certainly did play a prevent of sorts in both the WCHA and NCAA playoffs, after they got the lead. It was, however, a high energy prevent that didn't allow opponent through the neutral zone, or at worst, stopped all rushes at the blue line. Created turnovers were turned into Sioux scoring chances. Very successful prevent , especially in the games against CC and MSU postseason. Actually they played it very well in the championship against BC with the score 0-0, but failed to convert the turnovers into goals (largely due to Clemmenson).