I can't buy that this is vandalism. This isn't a small town, and neither of us are from here (no childhood enemies here). We are both professionals who have professional coworkers. Again, this is a seven year long issue.
The Atomic Ass and Ogre are thinking along the lines I am. Unfortunately the only other way out of the subdivision would require some actual 4-wheeling, and I can't imagine the kind of letters I'd be getting from my lawn care service after a month of that route...they already complain that I don't sharpen my mower blades enough.
2busa, my wife would kill me if she caught me throwing the wheel and tire in the swimming pool. In any event, if I move that wheel/tire combination to the rear the leak will probably stop...just as it did when I moved the leaking right front to the right rear during tire rotation a year ago...that previously leaking tire/wheel combo hasn't leaked since.
I think going to 18 or 20 inch rims and stiffer sidewalls may help if indeed it is the force of the turn causing the sidewall to flex enough to let a little air out of the bead. Spending $1000 or more on new wheels for a $5000 vehicle is something I would have done when I was twenty though...though that equation would have been more like spending $500 for wheels for a $300 vehicle back in those days.
For $1000, I'll just air the tire up.
StromBusa, you're absolutely correct. I should make a routine of checking this tire weekly, as The Atomic Ass suggested.
Thanks again all for the thoughts. Like I wrote, this is a bizarre thing.