I have a rental property and the tenant has been taking showers for years and took a bath for the first time, and voila, water leaked down into the living room onto the first floor below. So, I did a complete test: removed the access panel and checked everything behind there-hot and cold feeds, drain underneath, and of course, the overflow. The tub was filled as high as it could be filled (over the overflow of course) and not a drop. With the test, everything was replicated except having an actual person in the tub. Now, of course, the obvious reason is that she splashed water over the side, which is a distinct possibility, but she said she didn't and in fact, this same thing happened to the previous tenant when she took a bath. And again, this is only with baths, showers are not a problem at all. Any thoughts?