well, if you run the math of that stat, it means Melo played 71 minutes at SF which is less than 4% of his minutes, so yeah, that seems an inadequate sample size that would generate too much noise for any worthwhile conclusion
but I think we saw enough of Melo last season to recognize what he can do and what he can't. If he's guarded by a lighter SF type, he's really good at using bully-ball to establish position and get his shot off. Against PF's, he still has moves that will get himself shots against slower PF's, but he's simply overmatched against mobile PF's and stretch-4's with length
on the other end of the floor, he's easily beaten by either SF's or PF's with decent handles. Melo simply doesn't have the lateral mobility or reactions to consistently play solid defense
the biggest problem on offense is his high usage and low efficiency. I know he can get his shots, but he was 12th on the team in TS% & 13th in eFG% which left him 11th in Offensive BPM and 15th in overall BPM. That he carried that kind of crappy efficiency but was 3rd on the team in FGA's was a major symptom in Portland's failures last season. He's not 3rd-option-good anymore which is why his minutes and role should be dialed way back this year