Toby's reply brought up another good point.
I tried t keep the scenario simple to eliminate confusion.
One thing I neglected to mention was that the projectors and screen sizes are going to be different. Therefore, the "Gap" I mention would need to be dynamic for each output of the TH2G.

In the example of a 6x8 screen next to a 9x12screen, 12x16 screen, I would use different offsets of course but I would also use this different "Gap Scaling" feature I am talking about so that an image would get 1/3 bigger each time so that Pink Panther (just an example character) would be the same size when we walks across the boundary of the small projector to the next larger projector, and so on.

If you get right down to it, I guess what I'm asking for is a global scaling feature per mix so that instead of just -10%, -20%, and -25% for edge blending and +n% for gapping, we would in essence have a range of +100% to -100%. (Something that might nicely become a range of 65536 steps or even 256 steps in the future, hint, hint).