Hey Guerilla...I did "think that over for a minute". In fact I've thought about the rather large disparity between the sizes of the Mini's gas port and it's gas bushing in the past.
just as a point of interest, my (582) 5801 came from the factory with a .070 barrel port. I don't claim to be any sort of engineer, but going from that, it seems to me that Ruger went the wrong direction when they decided to drill the gas port in your shorter barreled model smaller. Or perhaps drilling it smaller was not by design, but the result of using a worn bit which had been re-sharpened too many times. I've seen that sort of thing a lot in regards to production facilities.
At any rate, I agree with you in that decreased dwell time would seem to necessitate increased gas flow in order to maintain reliability.
Hopefully, the .065 bushing which you installed will solve your problem. If not, it may turn out that you've been working on the wrong end of the mule, so to speak.