Overfilling may increase the rate of oxidation as well due to windage (the crankshaft sucking up oil as it spins very near the surface) or the crankshaft actually striking the oil. The crankshaft is designed to stay clear of oil. If it dips into it, or even gets to close, it will make a lot of splash, which creates a mist that the PCV will readily suck up and consumption goes up. The splash also exposed the oil to more oxygen, which increases the rate of oxidation. It may also cause foaming. The excess splash on the cylinder walls may overwhelm the oil control rings and increase consumption in the cylinder, thus increasing carbon deposits on the cylinder walls and combustion chamber. The crankshaft dipping into the oil will also cost power and that's why HO engines use windage trays to keep the crank free of the oil. Constant dipping into the oil may also increase oil temp due to fluid friction and there may be a cumulative shearing effect on the oil as well.
How many of these things will be issues depends on the engine. Given the manufacturing variances I've seen over the years, inaccurate dipsticks etc., the oil level may be an inexact situation anyway. In a few cases, I have found exact information of where the oil level is designed to be in an engine but the dipstick is off from that for whatever reason. Some Land Rovers and BB Mopars encountered in years past come to mind. Overfilling may put you to rights or may put you way, way over the top.
Other than the high speed cornering aspect, which I'm sure most of us face on a daily basis ( : < \ ), I can't think of any good reason to do it. And not all cars are susceptible to it. To overfill so you don't have to bother opening the hood later to check it seems the height of laziness.
