There are times when "tradition" wins out for me over modern materials or methods. Repairing wooden canoes is one of those. I much prefer reproducing original materials and methods to the greatest extent possible, particularly on a Willits canoe (call me sentimental) for a couple of reasons.
One is because that is what the Willits brothers would have done, in my opinion. They changed very little in how they built or repaired their canoes in over 50 years of production, and it worked. I've seen many canoes that sported repairs done by the brothers, and they are masterpieces of fit and function, and, with the exception of when they sistered in pieces in a gunwale, were accomplished without glue.
Another reason is that by using original methods and materials I'm usually not doing something that is irreversible. Using epoxy to seal a joint, while effective, will not allow anyone to do anything to the wood in that area without removing it altogether and replacing it. Maybe not a real big deal in some cases, but perhaps so in others. The Willits brothers recommended dealing with minor leaks by forcing their "marine glue" into the cracks, then cleaning up the excess with gasoline. I've tried that a couple of times, but have been unsuccessful in plugging the leaks that way, hence the varnish and sawdust method, which has worked for me.
Of course I don't go to extremes here, either. I don't use machinery that is driven by a central belt drive like Earl Willits used for milling parts, and I haven't tried to reproduce the now extinct varnish brand they used (although I have tried to reformulate their pine tar compound). On the other hand, I don't go to the other extreme of sealing leaks by encasing a canoe in fiberglass and resin, which at least in the short run, is very effective in solving the problem.
In dealing with all things wooden canoe-wise, I follow the medical adage of "first, do no harm".