I have just tried to reproduce this and am unable to. I will be adding my attempts as a unit test to verify that programatically it also fails to reproduce, and also to ensure that if a regression such as this ever comes back, it will be caught by unit test.
However, as I said, I am unable to reproduce it. The code so far is heavily unit tested, and two independent deployments (web1 and web2) should *never* reach inside each other's deployment folders at all. This is extremely unlikely and basically would violate the entire structure of the codebase to be able to do it.
If the items were inside an ear together, it would be *slightly* more likely to happen, but even then, our unit tests are fairly extensive and becoming more-so every day.
I would be glad to post up a zip file of the respective projects in case you would like to use them to reproduce. But I've been trying all morning and everything seems to be working as intended.