I know... and I will be getting the proofhide, but in the meantime, since the saddle itself is black and there's no darkening in the forseeable future, I think I'll just occasionally (i.e. only after getting wet, etc) use this until I can get some.

It's not viscuous like neatsfoot oil or other oils that even Sheldon Brown recommended 'soaking' saddles in... There are very few things from Sheldon's site that I'll disregard, and the 'oil soak' for leather saddles is one. still, lightly dressing the saddle so the summer dryness/dampness doesn't harm it can't hurt too much. Trust me, if the dressing contained tallows or patroleum products, they wouldn't touch it. I know my leathers.