I don't KNOW. . . but have an opinion.
I don't see having bypass when cold makes engine warm up quicker. I think It would make it warm up evenly. circulating flow.
running a centrifical pump "dead headed" is likely to cause cavitation, which eats away the impeller AND cause "loss of prime" ie no flow when needed
opening up the heater when cold could serve the same as allowing the design internal bypass. don't other engines have a bypass hose that continuosly loops, wasting flow that should go to radiator. at least the cleveland design doesn't waste that bypass once warm.
but I haven't sleep at a Holiday Inn in decades