That is also a GREAT idea !!
My incubator is rather small, it fits up to 6 egg boxes (2 shelves and bottom) so I'm not sure I need a dummy tub. Most likely I will only use the middle of the incubator. I have 3 snakes breeding, but not sure all will take. Its my (and theirs) first try.
I guess I will test run the incubator and test temps on all levels, and also run a "test" tub ahead of time, with substrate and everything but the eggs. Try out a few levels and temps and see what happens.
So which thermometer do you all use ? I know Accurite is a favorite. Any model numbers ?