It's my understanding that the reason behind the main gear oil bypass system was because the transmission could not run 30 minutes with no oil. It was thought that any loss of oil would occur in the external oil cooling system, so if you stop oil from being pumped to the cooler and trap it inside the case you have your 30 minutes. Apparently the transmission was run with a small amount of oil for a long time, enough to satisfy both the FAA and CAA, but with the caveat that below 5psi you land immdiately.
The tragedy of the irony on this forum is the spirited debate between the 225 and 92 groups and that both types suffered catastrophic transmission failures. Aviation always learns from its mistakes, often at a terrible price, so, hopefully, positive things will happen in these cases.