I spent 5 minutes looking over stats before I posted. Here is what I'm looking at from KenPom. For those not familiar he charts the "Four Factors Concept" as percentage which removes Tempo from the equation.
Our offensive rebounding % don't quite match but the tourney team was better at protecting the glass.
Steals are a subset of turnovers and an indication of style. Some teams aggressively force turnovers that way, some don't. Our turnover % was higher in 2014-15 than 2013-14....that's the number that really matters.
The 2pt/3pt stuff is all a subset of effective FG, which normalizes the values of the shots. Our eFG% was lower in 2014-15 than 2013-14. You can hem and haw over allowing more 3s and more 3s to go in but our strength on the 2pt shot negated it.
You're right that overall the offensive numbers in all of college basketball went down from 2013-14 to 2014-15 and so you'd need to have a relatively lower defensive points per possession than the previous year. However when you look at the adjusted efficiency ( accounting for quality of offense, locations of the game, give more weight towards games towards the end of the year) both teams were top 25.
Not included previously was the foul rate...we fouled more in 2013-14 than 2014-15.
I think there is a good argument that the 2013-14 team was essentially two different teams...one with and one without Deverell Biggs and one that probably was overall a better defensive team at times. However, overall the notion that the two teams aren't particularly close over the course of the year and that the 2013-14 team is easily better is something I completely disagree about.
I would concur that adding up all the things that support one's point of view is quite simple.