I have found that if one leaves Mas until it is thumbnail hard the next coat can form meniscus areas and draw away from the under coat. This may be because its low viscosity allows surface tension to come into effect.

I prefer to overcoat with Mas when it is still a little tacky. Overcoating tacky mass has worked very well for me and has the added benefit of speeding up the job. At 70 degrees I find around four hours between coats is about right. That is with slow hardener.
They claim that the fast hardener doesn't blush, but it does. I only use fast for glueing. I don't even use it for filleting. I really cannot be bothered trying to scrub and scrape blush off. I'd rather just wait a little longer and do something else in the meanwhile.

This is one reason that I prefer not to seal coat, because laying cloth onto a tacky surface just does not work for me. The cloth would most likely break the surface tension anyway, but I prefer not to find out. One day I'll do a test.

I use to find the glassing a bit of a chore, but recently I have actually been enjoying it. The reason.... I have finally managed to get my workshop temperatures up high enough with my bubble wrap tent.

The sides of the tent fold up onto the roof when it is not needed.