I'd bet for mirror issues. Mirrors are out of sync and yum does
crazy
things then. Remove mirros list and use baseurl instead.
I tried that, but it looks as if the master repo has a primary.xml.gz file
that is woefully incomplete compared to the actual directory contents.
I think the mirrors are in sync, but they are synced with trash (or were
last night when I was looking at it in detail :-).