Patent trolls are by definition non-practicing entities. How does having your own patent defend against them, if they're not actually producing anything that would infringe it?
Patents are also not supposed to overlap each other. However -- and again this was made startlingly clear by NPR -- they do, and by the tens of thousands.
You're making the mistake of believing yourself to be in a world where reasonableness prevails.
It would be a weak form of defensive patent aggregation (http://en.wikipedia.org/wiki/Patent_troll#Defenses), but it would still be better than nothing.
My larger point is that, by vocally opting out of the patent game, the author of the original article has practically painted a bullseye on himself. Averring yourself to be above the fray seems to me to be a sure-fire way to be victimized yourself.
Now, your own patent could in some circumstances be used as prior art against the patent troll... but if that's all you're using it for, why not just publish everything you're doing? Publications are prior art just as much as patents are.
What, exactly is this "basis"?
Note that a given thing can be covered by multiple patents, owned by different people.
Yes, patents can be prior art against other patents, but you don't need to own a patent to use it as prior art.