Groce did overachieve that year, no doubt about that. Also, let's not forget the addition of McLaurin. Independent of just pure stats, Sam was undersized, but still provided some very valuable minutes in the post, which helped open up the perimeter for Paul.
Obelix, I appreciate a lot of your takes on this site but if you really think McLaurin had any effect on Brandon Paul's perimeter shooting, maybe I should rethink my attitude towards your posts. BP had space to shoot because DJ and Tyler could also knock down shots, not because Sam had a respectable post game.