Yep... don't see any reason to add markers on the inside of a clip. Add all the markers you want to the outside.
If you start adding things like b-roll to the inside of a clip, it gets promoted to a compound clip, with all that entails.
Good luck.
---------
Don't live your life in a secondary storyline.
Mark Morache
FCPX/FCP7/Xpri/Avid
Evening Magazine,Seattle, WA
http://fcpx.wordpress.com