Being from another platform (and new here) I tend to agree...NEVER run 0w20 oil.
That is to get the best mileage, but is not at all best for the engine, especially the valve train.
The thinnest oil I would ever run if 5w30, and 10w40 is better after the first year or so.
If you are worried about over pressure, don't.
The oil pump is positive displacement, and pressure controlled entirely by the relief valve.
So the weight of the oil can not possibly effect oil pressure.
All cars running 0w20 are having premature valve train failure, like timing chains, camshafts, etc.
Do you have data to back your claim?
Bob.
EDIT: I drove Twin Turbo 3000GT's and ran 20W50 (summer, a bit less in the winter)...