Saintsfanfl
TUG Member
My info is about 2 years old and suggests that the trade power and quality ratings are independent but work together. Yes in effect it is trade power but it is (or at least was) a different processes. The resort won't necessarily be blocked on resort quality, the reps can override it to trade down. But it also works both ways as you can't move up or down TOO much though as the time draws nearer, the restrictions are reduced.
Yes, it is only blocked from doing it yourself. You can always call and do it. On trading up I have to respectfully disagree. I can show you an example right now of one of my resorts that no Marriott can view, but that same resort can see units at the highest rated Marriott resorts. The block filter only goes one direction and it has been this way for at least 5 years. What you are describing about restrictions being reduced as time draws nearer is the trading power (or resort "quality", but not the block filter).