In that post it says:
Jerry at Fasco said the best time to put the second coat on is while the first coat has the same tack as masking tape. On my boat, I believe it was about 2 hrs after I applied the first coat. If you wait overnight, the first coat dries and becomes very slick, so you'll have to scuff all of it up again to get a good bond with the second coat.
Allowing any epoxy product to 'tack' first and then apply the follow-on coat allows that next coat to chemically bond with the previous coat, at least from my experience w / all major brands of marine and gunsmithing epoxies. Also never mix more than you can use. And mixing in 'too big' a container (tub, etc.) can cause epoxies to 'cook off' and cure on you in the pot or almost erupt in flames !!! , due to the heat generated. When doing large surfaces, I mix then pour it into old cookies pans, as the wide/bigger the surface area and less deep ... the longer it will take to set up, i.e., longer pot life.
But as with anything, if still unsure ... follow the directions included with the product or call FASCO for technical assistance.