I lost the bet and paid my dues. I consider myself a true scientist (albeit an untrained one) so I'm always willing to start with a theory and seek out information that can prove it either way, and accept the conclusion and change my theories to fit the evidence and the proof like a real man.
While it seems like the air pressure is the only wildcard factor here, and the size of the structure may have an effect, for the most part, my myth is busted.
I realize that Pascal's Law is the key here really - "
Pascal's law or
Pascal's principle states that for all points at the same absolute height in a connected body of an incompressible fluid at rest, the fluid pressure is the same, even if additional pressure is applied on the fluid at some place."