You keep saying that. HOW did he regress? Just because you keep saying it, doesnt make it true. Want to look at some numbers? He improved is PPG, APG, TOPG, FG%, and 3PT% (just to name a few), all while playing four less games. Look at the numbers. Now, how in the WORLD is that regressing?
http://stats.washingtonpost.com/cbk/players.asp?id=97656
From looking at his career averages I can see how each could come to the conclusion you did with the criteria being regressed from his junior to senior year. It is an entirely different story though if you would have added his sophomore year into that equation. Since all three years were very close in minutes played per game this is my opinion which might be a little different than either one of yours but I am merely stating which of his last three years did he have the best numbers.
Sophomore and Senior Tied for Same # of APG and least TO per game.
Sophomore best year for most Blocks, FG% and 3PT%
Junior best year played most minutes per game, Rebounds, FT%
Senior best year for PPG, Steals per game, Worst year for fouls but still less than 2 average per game
I felt like he deserved more playing time as a freshman but I guess Fran didn't see it that way. By the above criteria I would say his best year was his sophomore year.