Good point Don Tomaso
My cordovan FQHH is only a few years old. Has had lots of water and creasing since new. However, I found that applying a thin smear of RM Williams Saddle Dressing actually brought the patina out even further. Now, when I crease or slightly twist the FQHH, that area is left with a nice bloom/fade. That'll probably be it for another few years. RM say this stuff will never go rancid. The consistency is somewhere between butter left in the fridge/out overnight. Not a liquid, so needs pressing into the leather with fingers. Warmth helps here.
I remember someone (possibly Jan Solo) who bought a bespoke FQHH wallet. The maker treated it with the same stuff.