Typically, the solvents/liquids in sealer will penetrate, but the solids won't.
I don't know, since Minwax doesn't need to be stirred, if the solids are in solution, or if there's some other magic chemical that would soak into the wood. If so, it would surely make balsa a lot stronger. But maybe at the cost of bouyancy.
I use Minwax, too ( thanks Nathan), but I've never soaked my lures. I just dip, hand to dry, sand with 220, dip, sand again, and then prime. I also use Krylon primer (thanks again Nathan) as a primer/sealer.
But then I seat my hook hangers and eye ties in epoxy, and epoxy the whole bait when I'm done.
Having said that, when I used rattle cans for primer, paint, and clearcoat, I used to just hang the lures to dry after I used them, and then shoot another clearcoat onto them. I always thought water intrusion was a fact of life with wood baits, something you just learned to deal with.
I didn't think you could make a wood bait water proof. It would be cool.
Please report you findings. It's great to have a testing lab on the site. )