Well, I've had a few responses directly to me and seen a few to the list- the responses are 50/50. Some say that the worn tires won't affect the alignment because the alignment is taken from the wheel position. Kind of makes sense, but the wheels are sitting on the tires. Others say it will affect the alignment. If you are one of these, can you elaborate on why? 

I'm driving a nearly 1,000 mile round trip this weekend to Buses of the Corn in Ontario, and I don't want to make the tires worse.

Ed