Depends on the engine, I suspect. But since the pilot checks the oil and secures the dipstick on her preflight, it won't happen, will it
I don't know if it would blow oil out of the dipstick tube on the Arrow engine - it's a long tube sticking right up to the flap. Never tried it.
My pet hate is when folks do the dipstick up so tight that I can't undo it without getting my hands filthy - or getting out my leatherman to grip it.