I doubt Cal taught them differently, its just they found out against UT that without Noel back there they need to play better D.
This was a good year and example to show how having an elite defender can sometimes be a bad thing. These guys allowed themselves to realize that "hey I just got beat, but so what, Noel will clean it up for me." While WCS is making strides, he isn't the elite defender that Noel was and now they are playing better D.