Quinn;
Most guys start their wrap, wrap most of the way to the end then put in a pull loop and pull the tag under the main wrap, if you get your loop in 10-15 turns before the end , you can pull the tag under 2 turns, cut it, then pull it under without the end of the thread coming out between the wraps. I start my wrap with the loop laying along one side of the guide foot, put the start tag under the other side, then pull the tag end completely thru when I'm done. Burnish the wrap, pull the tags one more time to snug everything up and trim right next to the wrap, nice and neat and no bump from the end of the thread, plus the thread along the foot helps wick varnish in the tunnel so I don't get any air bubbles.
WC, I have wet sanded, I find dry sanding works as well for me.
C13, When I do an impregnated blank, I sand before the last 2 coats. The longer you wait between coats that you intend to sand the better as far as I'm concerned. The only time you need to be concerned about getting the next coat on is with polyurethanes and lacquers that need the first coat to not be cured before the next goes on in order for it to bond.Even with those finishes, all you have to do is scuff sand if you've waited too long.
john