I build fine furniture and sometimes I use polyurethane varnish for a finish. I don't wait for the individual coats to fully cure before I recoat and I have NEVER had a problem with the finish. (and don't tell me that a table top isn't in an abusive environment - hot pans and plates/bowls and spilled liquids as well as condensation is NOT friendly to any finish.)

However, as a tip to get good smooth coats without as many runs and drips, thin the varnish 75% varnish to 25% Naptha and wipe it on with a paper towel. This should dry for a second coat in 4-5 hrs and 2 thinned coats is equivalent to 1 coat unthinned. Let dry overnight. Scuff sand and recoat 2 more times the next day. Scuff sanding isn't all-out wet sanding, it's just a light scratching all over the surface to give a good mechanical bond between coats. Tack off after sanding to get rid of the dust. Let the finish rest for a whole day or 2 if you plan on putting on more varnish after the second day. Scuff again before the 3d coat. Once the varnish is dry (a week or so) rub it out with either steel wool (or scotchbrite) and wax or auto polishing (NOT buffing) compound. This results in a satin finsh. For a higher gloss, use automotive swirl remover in a buffer after rubbing out the finish.

FWIW, mat finish is a dull nonreflective surface. Semigloss is a satin surface - shiny but without the reflective qualities of gloss. Gloss is, of course, a mirror finish.