You're missing the point. The point is Reggie Evans, inspite of his offensive game not translating from a lower (college) to a higher (NBA) league, still, I repeat, still, shoots 47% from the field. Because he knows he'll be out of the league if he jacks up 3s with 10 left on the clock. Or shoots <40.
the point is that he still have offensiv abilities, and not like the defensiv specialist who learned basketball without having a basket you want to have here.
When the average Big men skill in BB would be 13 for a league, an Evans stile player would have something like 10 IS and 15 ID. if you want shooting percentages like the NBa, you probadly need a average of 13 IS compared to 10 ID and evans have it maybe the other way round.
I hope you see my point now? In real Pro leagues there aren't people who can not score, even the defensiv specialist would be offensiv options one level below.