I'm sure Pop remembers how he used Malik Rose. Blair has similar qualities. Active hands, good rebounding technique, tenacity, similar height, not quite as quick on his feet but terrific wingspan with a knack to create loose balls.
Sealing for TP, Manu and RJ drives. Big soft mits to receive wrap-arounds. Setting strong ball screens on the wing. He can be a great asset to the offense.
Blair guarding lifted Bigs is a problem that needs to be ironed out, because teams will draw him out and exploit DeJuan and his lack of experience.