I'm guessing that new oil pump housing seal is an attempt to prevent the scavenge side of the pump from sucking air from the cam chest instead of oil from the sump. The actual problem "appears" to be related to the oil pickup in the sump, and I've seen lots of discussions about that in the other forums. Harley made some major changes in the case design versus that of the TC, which didn't have this problem unless the oil pump became worn or damaged. I seriously doubt the seal on the pump is the root cause of the problem, but a redesign of the cases would be a more expensive proposition plus a very much more expensive approach if they are forced to apply a fix to the earlier M8's. In other words, a band-aid fix. If it works, fine. For purists who want the root cause fixed, I'm guessing that will be put off by the MoCo until it becomes time to retool for other reasons.
JMHO - Jerry