When one refinishes a bow. Is the oil or final coat applied over the fiberglass or just the edges?

Over the glass. I lightly sand the whole bow with 220 and apply the finish.

The finish needs to go over every inch of the bow.

I've only built two bows and I finished one with spray on poly-somethingorother-ethan, the other was with wipe on poly.  I doubt that I'll ever use anything again other than the wipe on poly.

One drop on my fingertip spread as thinly as possible.  When it dries, repeat the process until you build it up as much as you want to.  

This creates a glossy finish but it can be brought down by various means.

*The key to any finish is in the prep work prior to putting the finish on, IMHO.

I have been using Minwax  Spar Urethane (satin) in the spray can. I usually put on at least 8 coats, which is just over 3/4 of a can. I spray the whole bow.

I put three coats of spray Minwax Spar Urathane on the glass and at least five coats on the wood.

Jim; PM sent