The only thing we can speculate about is what we would have done in his shoes, unless he provides a convincing insight. If it was me, and I cared about a project of mine for the sake of the project and thought it was a vital project (as opposed to one of my tinker toys), I would have open sources the whole thing, no dual license. That way nobody can "steal" it from the community, by buying some company. I would also have tried to give it to someone like the Apache Foundation, so that when I die, my project does not.

On the other hand, if I thought my project was going to be a cash cow, I would have done exactly what Monty did, except the whining after the fact. I think if I buy a car, then sell it to someone and that person sells it later to my arch nemesis for a discount and he plans on wrecking the heck out of it, my screaming about how this is not right is not going to attract many supporters, is it?

When you say "I would have open sourced the whole thing", what you really mean is "I would have BSD-licensed the whole thing". There is no difference between dual-licensed GPL code and straight-up GPL code. In both cases, your rights as an end-user are identical. In neither case can you pick up the codebase after it's sold to Sun and start a new commercial endeavor on it that isn't GPL'd.