I'm pretty sure that if you wear a DON'T HONK AT ME jersey around here you gonna get honked at.
Two wheels good. Four wheels bad.
Yeah, I can't imagine those really generating a positive effect on drivers. I can imagine someone reading the "don't run me over" jersey and saying, "Hey, never thought of it!"
Seems to me you'd want one that says "Saving gas for you"- get the idea across that me riding a bike benefits you.
"be careful this rando stuff is addictive and dan's the 'pusher'."
How about a "don't post the same jersey thread every month" t-shirt!