As I said in my comment, I agree that the tenant object should be cloned/copied. However, I don't think it's excessive to ask for a performance test for this. This code is executed hundreds of times per second, and I'd like to make sure that it doesn't significantly decrease performance before merging this as is. If we had the nightly performance tests set up, I'd be happy to merge and make a note to check in the morning, but we're not entirely there yet.