Fair enough! For my own edification though, can you explain why it would fall apart? Mechanics aren't my kind of engineering.
Russian did something similar, but they war more a test bed, and those submarine was build more stronger after more modern technology, than this old German submarines, for just by adding the launcher there, you are cutting trough the pressure hull, that also act as the hull of the submarine it self.
Look at it this way, take an egg and try to crush it, very difficult to do. But what if you make an hull right thru that egg, now you can crush that egg with two fingers. A submarine that dive, operate very deep, and the pressure that are pushed on the hull at those deep is similar to when you try to crush the egg in you'r hand, but only mush stronger... a submarine have to withstand several tons of pressure...