Sheldon Brown also recommended oil soaking. My suspicion is that some of the saddles he's talking about were already toast before the wrench touched them.

With so many different results, I suspect there's some significant saddle-to-saddle variation in addition to the ass-to-ass variation. It wouldn't take much, just the natural variety in thickness and grain of the leather. Hand made saddles are going to be somewhat inconsistent (someone on another thread got a new lopsided Brooks). And then there's model: my trampoline of a B67 isn't going to wear the same way a narrow B17 does.