Jay-
Just to be clear: For cockpit rims, you are suggesting glass/epoxy on the topside and underside, but just epoxy on the edge of the rim?

Yes. However, this summer I was working on an early boat and I did the 1/4 ply rim on a stacked base. The edge was opening up in a few places and I did a wrap. In my arsenal of epoxies, I have some Raka fast. In the warm sun it will harden in a few hours. I used that. I wet out 4 oz glass cut on a bias and wrapped it under the lip and it was a terrible job. Left it in the sun 85 degree day and a few hours later it was like fly paper. Very sticky. I easily wrapped the glass tight around the lip. When people have trouble with that, they didn't wait long enough. There will be a point when the tack will be like the underside of duct tape. It will hold tight. My edge thickness was about 1/16 and rounded. Did I need that - no. I could have just coated it with a few coats of epoxy. but since I was putting glass on the top of the rim, I figured why not. And because I wet out the cloth from the beginning with fresh epoxy, it stayed transparent. If it didn't hold, I would have just used an exacto and cut the cloth at the edge and coated the edge later.