May have to disagree about the higher pressure not making the rear seal leak more. If the mains are worn enough to merit more oil pressure with a more agressive oil pump then the oil has to go somewhere. If that rear bearing has enough slack to let much oil by, then some has to get to the seal. If the oil can't drain off the seal fast enough, it has to go somewhere, usually out. Kinda like what happens to the automatics when the front pump bushing gets bad, sometimes will push the seal right out.
If oil pressure is low after the engine is warm, it's time to look at bearings at the very least.
