J. Clarke wrote:

Even though Bondo wood repair did not last long, it did last longer
that what you suggested.

The poster and video people were shills for "Better to use Abatron."

And if you look at their bad example of Bondo, it's pretty clear that
it's really a bad example of surface prep.

That and the fact that it was used so extensively. Bondo works well for
smallish areas but over large areas it will eventually fail. It fails
because the wood expands and contracts differentially to the Bondo. The
epoxy material material they promote will do the same thing, just slower; it
is slower because epoxy has a stronger bond than does the polyester resin
used in Bondo.

The exception is plywood and it is an exception because ply doesn't respond
to weather/humidity changes as much as solid wood.

Time was that many home built boats, usually trimarans, were built with
plywood which was then covered with layers of fiberglass all of which were
adhered with polyester resin. In fact, I have a pram I built eleven years
ago in that manner; it is still good as gold. Numerous commercial boats
were built in the same manner; the Newport 40 ketch was one.

Other than just replacing the rotted wood in the video, the guy would have
done better by cutting it out to good wood, then building it up with
plywood.