Thanks RTK for responding. I should have narrowed my question to a direct comparison of 50:1 at 50:1 and 100:1 at 100:1.
I never hear anybody mixing 50:1 at 40:1 but most people running 100:1 are mixing it at a lower ratio. My only guess is that the mentality
is that mixing at 100:1 makes the engine more succeptable to damage if improperly tuned than running a 50:1 at 50:1. Maybe that mentality is correct.
I have to agree that running a 100:1 oil at 80:1 will leave more room for error. But then why not start running 50:1 at 40:1.

Why do people feel that 50:1 oil will offer more protection to an improperly tuned engine than a 100:1 mixture? Don't take this out of context. I am asking this question with sincerity.