jimmie jam said:
i have never proven extended durability by layering...
Please don't take this as an :argue but rather as simple discussion. This is one area where my experiences/opinions can sometimes vary from those of people with whom I'm almost *always* in complete agreement. I've pretty much adopted a "here's my experience, see if it works that way for you" perspective on this, as opposed to a "hey, it works for me, so what's *your* problem" perspective.
I've had differing experiences when layering waxes and sealants, from zip (UPP, non-spit-shined Souveran), to "well, maybe, but not without spitshining and I dunno even then..." (Meg's #16), to incredible improvement (KSG, Collinite).
The differences when products *do* layer for me are pretty dramatic- adjacent sections do/don't keep beading the same way, stay slick, shed dirt, most any criteria I can think of are obviously observable. When the differences are *not* dramatically obvious, well, they aren't

and subtle differences aren't meaningful to me.
I wonder if we approach the layering and/or the evaluation of same in radically different ways :think: There are probably a whole lotta explanations for our differing experiences, but if I didn't derive a dramatic increase in durability from it I simply wouldn't bother (and I *don't* with products where I don't see any benefit, I don't even bother spit-shining 99% of the time- if a product needs that I usually just do one coat and say "good enough").