> Software development is like plumbing really, so a good manager of a pipeworks and plumbing company might actually make a good manager for software companies as well.

No, wrong again. Some software development tasks are like plumbing, but that misses a lot. Your claim in sort of like saying since the Wendelstein_7-X has wiring, the manager an electrical contractor would be good to lead that project.

Plumbers and electricians more or less solve the same problems over and over with slightly different parameters, and because of the repetitiveness, they can do a good job by following (a hefty number) of rules of thumb (the building code). A software developer isn't going to go far just throwing design patterns at a problem (though many bad ones try).