Unless my definition of 'callous' is wrong...
I greatly-avoid what I've considered to be callouses! I work ointment into my finger-tips every day! Lately it's been 'Aquaphor' brand (my wife suggested it), but for years before it's been a Mary Kay product - I can't remember the full name, but it's "night"-something; it looks like orange axle grease.
As far as I understand, a 'callous' is like 'hard skin' or 'thick skin'; like a skin-thig! The skin on my finger tips is pretty-much baby-soft, but the tissue behind it is tough like tire rubber or something. ..Now for the first year-or-two of playing bass I got definate callouses - like the kind that would show-up on a finger print; now-days I pluck with much-more refinement and finesse (I'd like to think!), and if I had callouses like that NOW, I'm sure it would screw-up my playing a little.
The only place I have what I'd consider a 'true callous' is on my thumping-thumb. This makes sense, as I haven't been thumping that much (working on it, but still most of the band-songs that I play and practice are finger-funk style).
Is my definition wrong? Is soft skin with uh.. 'hard meat'... (well - you know what I mean) considered a "callous"?
Joe