Nice shirt. (As David Silverman noted, there are two kinds of preachers: liars and victims.)
I've had my share of discussions with JWs, dating back to 2010. I was polite with them, but utterly unwilling to give any ground to them and indeed, had answers to their questions that I don't think they expected. After 2012, they quit coming, though, I suspect because they realized they were out of their weight class. I think that politeness is important, too, because it takes any opportunity to complain out of their quiver, and considering atheists are still considered the least trustworthy of any major societal group in the US, how we conduct ourselves is no small matter.
Still, if you've had your fill of their intrusions, I have no problem with your approach.
Very good point, Loren. We should indeed use all our well-learned politesse (even though we know they can't lay our souls to waste since they don't exist.)
A couple of years ago Dr. Kellie kept us abreast of another strategy for discouraging door-to-door proselytizers in "What Boobs are Good For".
LOVE the shirt - wish I had the guts to wear it!
There's others, Elizabeth ... lots and Lots and LOTS of other T-shirts to choose from! Trust me! [BIG grin!]