As for 1- Shouldn't have any effect at all. Unless you leave it for like a year. The majority of the oil will drain to the oil pan, but will leave a residual film. That is all that is needed for startup. But I would let it idle for a few moments once you do start it.
But 2- it will make the fuel mileage go down. You just can't get a good burn. If the ignition is not set up for such a large spark gap, you may not be burning fuel as effectively.
But 2- it will make the fuel mileage go down. You just can't get a good burn. If the ignition is not set up for such a large spark gap, you may not be burning fuel as effectively.