ezo
Get off my lawn!
If I wanted it smoothed out I would probably do:I'd quickly smooth that out to
9-12 +0
13-15 +1
16 +2
17 +4
18 +6
And would then ask myself how (or if!) it would work with stats beyond 18, which while uncommon are certainly achievable in BX or 1e; never mind percentile Strength which is, as usual, its own can of worms.
13-14 +1
15-16 +2
17 +4
18 +6
But frankly, even that isn't high enough on a d20 to really make the contested concept work IMO. But, hey, what I would like others would find crazy LOL!