clearstream
(He, Him)
The intuitions pumped are different. 8 and 10 say, no difference in spells memorised. 8 and 20 then, a difference of 5 spells. It is easy to draw from that a less effective short term and working memory. And less attentive, flexible, and quick.I mean, just adjust the numbers from 5% to 40% and the same arguments are applicable.
Judging a 5% difference between two people is different from judging a 40% difference. In height 6 foot versus 3 foot 8 inches or so: easily visible.
Thinking of the d20 range, the floor and ceiling are in markedly different places. In Tier 2 with Expertise 6-25 versus 14-33. The 5 Int PC might very infrequently solve a very hard problem. The 20 Int PC can solve one in five nearly impossible ones. That they can attempt such puzzles with any expectation of success is remarkable.
That all said I would favour playing lower ability scores as nearer the middle, to avoid representations that may not be well-informed and are probably impossible to sustain. So I'm more envisioning that if one wants to portray exceptional talent in an area covered by an ability score, one reifies that with the score itself.