Bummer
For years, I subscribed to "The Old House Journal", which uses the term "remuddling" for home-remodeling jobs that violate the history and character of the house. It would be nice to come up with a similar term for the canoes that aren't, in fact, "restored"... which have, perhaps, been made usable again but which face all the potential problems involved with fiberglass... something catchier than "glassed".
I take issue with the term "restoration" if the canoe is not, in fact, put back to a reasonable semblance of its original condition. Using fiberglass, to my mind, would not be a "restoration" even if it didn't have the potential of creating problems.
A sponson canoe is heavier than one without sponsons, and when fiberglass is added... well, it probably wouldn't be a canoe your car could wear like a hat.
Kathy