I think you're right here, Don.
I know of a Tour Master with only 91 ranked rounds played. On his Profile, it says his average is 61.00. But, when you look at his stats under (scoring), it says 67.00. He plays tons of match play. His stats (with all due respect) reflect more closely, those of a Tour Pro, not a Tour Master.
I'm wondering if he believes he will make Legend without playing anymore ranked rounds? It appears he's just sitting on that 61.00 average and not playing any ranked rounds, as he knows his average could likely go up if he plays ranked rounds that aren't really low.
And, IF WGT will advance him without his playing additional ranked rounds?
I have looked at his scoring history. He didn't even play the min. required rank rounds as a Master - but, was elevated to Tour Master; most likely due to all of his match play.
Well, he just might make it to the Legend Tier, but, I have no idea how he could possibly compete - not with his stats.
I have put in my minimum 50 ranked rounds as a Tour Master. My average won't go up, as long as I'm still a Tour Master, only down. But, I don't see how it's fair that I am required to play a minimum of 50 ranked rounds - and work my average down to 61.00, but, that other Tour Master doesn't have to meet the same criteria.
So, I think you're right - WGT makes exceptions to the criteria that it shown above for the various tiers.