Okay. I will definitely double check leak down when hot before tearing anything down but it sounds from your post that the area to be looking is in the pistons/rings/cylinders.
If I read into this correctly, you are saying it is possible to have a failure point within the piston/cyl. system that would yield the symptoms of oil smoke at limited rpm ranges? Presumably the higher load at WOT/high rpm works to seal the rings?
I'm looking to solve this problem in the most efficient way and learn some more stuff along the way.
Thanks!
David