Utter claptrap. I don't know about No Corrode as I don't know about it and hadn't mentioned it, but Vasaline will insulate terminals .
Vaseline is mostly petroleum jelly (petrolatum) mixed with some minerals, micro-crystalline wax, and possibly a fragrance - all of which are also non-conductive. Pure petrolatum is an excellent electrical insulator. And, Vaseline (petrolatum with other “impurities”) is a very good insulator.
So it's pretty obvious that even a small amount will increase electrical resistance.
By the same token that doesn't make you correct either Tony.
I've never dressed terminals and never had a problem. I simply make sure they're clean.
Anyway tell me, what exactly is the advantage of dressing the terminals before assembly as you recommend, over dressing the assembled joint as I described? If the assembled joint is properly dressed nothing will get between the mating faces. Your method can only be disadvantageous as far as I can see