I use --pretend daily and very often I see that portage wants to update/downgrade a package. Most of the time it actually doesn't downgrade as the package it wanted to initially remove was protected. The --pretend output must take into account the protected package and not report a downgrade if the package needed to be downgraded is protected.
Sounds like a dupe of #4698
*** This bug has been marked as a duplicate of 4698 ***