Answered
Link and Group not consistnet
I can remember when A/V tracks were dependently linked, my default. But, for a very long time now, I I often them Unlinked; even thought the menu shows them Linked.
If I toggle the Linked opption, they will link up but if I add an edit they well become unlinked agaoin. So, except when I see the offset, I can't be sure whne they are.
This is also true for Groups. I can group clips, but they come apart when dragged.

