I'm trying the Minwax/Rustoleum process for the first time, and I had to do something twice before I figured out it was a good deal.
Minwax is really a pain to sand. It balls up into these long skinny cylinders that you have to keep brushing off the sand paper, and it's never quite smooth.
I had run into this on my test block, and made some sanding sealer by mixing Polycrylic with talcum powder (just like making sanding sealer with dope). So I got to 'that' stage in this finishing job, and I got out the sanding sealer. Boy oh boy, what a difference! Polycrylic alone is the same pain to sand that it always was, but if you mix it about 1:1 with talcum powder it turns into stuff that sands just like lacquer primer.
What I don't know is how much I've affected adhesion -- I may have just made myself a plane that will suffer from the "Minivan Hood syndrome". We'll see.
But it's nice to sand...