Here are the last 20 #12 picks:
Taurean Prince
Trey Lyles
Dario Saric
Steven Adams
Jeremy Lamb
Alec Burks
Xavier Henry
Gerald Henderson
Jason Thompson
Thaddeus Young
Hilton Armstrong
Yaroslav Korolev
Robert Swift
Nick Collison
Melvin Ely
Vladimir Radmanovic
Etan Thomas
Aleksandar Radojevic
Michael Doleac
Austin Croshere
What exactly are we trying to accomplish with this move, again?
Last 10 years : Saric, Adams, Burks, Henderson, Thud Young were all OK picks (to say the least). We are talking 5 out of 10 picks. Not to mention, the jury's still out on Lyles, Taurean Prince. Heck, I really liked Lamb at the time as well.
Not to mention, you can't just look at pick 12 and say see, you have to reasonably look at picks 12-15 because those are all reasonable selections for pick 12. That gives you a much better look at the type of player that is reasonably available at 12. I mean take 2011, 12 - Alec Burks, 13 - Markieff Morris, 14 - Marcus Morris, 15 - Kawhi Leonard, 16 - Nikola Vucevic, 17 - Iman Shumpert (I went to 17 just because it was so deep that year). Obviously that year is a bit extreme, but you can't just look at pick 12 and say see it sucks, when picking at 12 gives you the ability to draft any player after that. Clearly though you can't just take 2nd rounders because that isn't reasonable, but dropping back a few spots certainly is.
I'm not saying every player taken at #12 is worthless. But how many of those players would improve our current roster in any meaningful way? Especially when we are trading away a quality starter?
And yes, you can also draft any player taken after #12. You picked a very high-quality year. Others look worse. In most years I see roughly 1 out of 5 guys that are starter-level or better. Getting someone better than Crowder or Bradley is pretty rare. Getting an All-Star is rarer: from 05-15, there were 60 players taken in the #12-17 range and I count 4 All-Stars (Hibbert, Jrue Holiday, Leonard and Giannis). Though I'm not even sure I'd take Hibbert or Holiday over Bradley at this point.
And then for each of those guys there are countless in the Royce White, Oleksey Pecherov, Kendall Marshall, etc. bin.
I mean, the Celts have four guys taken in that range: Kelly Olynyk, Terry Rozier, Tyler Zeller, and...James Young.
Not sure I see why we'd want to take one of our starters and replace him with someone in the same quality range as the current guys who can't get off our bench.