Have we ever played a zone under BU? I don't remember us playing one even for a possession. I do agree with you - with the way college basketball is today with so much turnover every year with transfers, freshman playing key roles - switching defenses down the stretch to give the other team something to react to seems like a really good strategy. It would be very hard for a freshman PG for example to react to a new defense being thrown at them at the end of the game.
However, BU is a better coach than both of us and doesn't play a zone, so I don't think we'll ever see one. When to pick up full court and pressure seems to be the biggest change he's making this year in-game. There are lots of nuances of course in how they are defending ball screens and when to double the post etc, that he will change mid-game - but it's the same man-to-man principles every possession, every game. I'm sure there is a philosophy if you want to be great at something you have to do it every possession and not mess around with getting them to play a good zone defense too