Joe, for you-know-what and giggles I'll do the 30 day gas-on-a-shelf test as you request but I have zero problems with 30 day old E10 gasoline in actual gasoline engines...so I'm not entirely certain what I'll be proving or disproving. If 30 days was an issue then the roads up here in Washington would be strewn with dead cars.

You didn't explain why your recent problems are attributable to E10 and no other possible cause, but I won't belabor the issue :-)

Cheers
DD