Re: ...for the jazz cats ...
Yes I remember, you also sat in on a class at Purchase.
To continue the discussion: who's the drummer's closest associate in the rhythm section? The bass player. How does a bass sound? Low and woody.
What part of the drum set plays most intimately with the bass? The ride cymbal. How does a ride cymbal sound? High and metallic.
Feathering the bass drum helps the groove because it helps your metallic sound marry with the bass' low woody sound.
All great players feather when appropriate.