Same reaction here. MOSIX was basically this idea developed for real. Turns out there are a bunch of secondary problems to do with namespaces and security, scheduling and resource use, topology, performance, and so on. In the end it never turned out to be all that practical, and I know of several efforts (e.g. LOCUS) that went quite far to reach the same conclusion. There's a reason that non-transparent "shared nothing" distributed computing came to dominate the computing landscape.