Congrats Chris! I stumbled upon this a few months ago now and have just been trying to flesh it out and see what works best. What my goal with this was is to do the switch so openly that the thought never even crosses their mind that the cards could have switched. Due to that thinking, I really don't like the idea of using it as a color change, or of using more than just my index and thumb. However your suggestion on the spread is very nice; I have been using it as a force pretty regularly and I actually execute it mid spread, which is fairly awkward and risky, but very convincing. I can see however how closing the spread and leaving it a little messy could give you a lot of leeway in execution, great idea!
Also as to the take, I through that in there on this video a few times just to try it out, however most of the executions in this video, and every time in actual performance, I do the switch entirely with the right hand. And after seeing how it looks getting the left hand involved from these recordings, I think I'm just gonna stick to the right. Less motion, and I cant see any advantage to getting the left involved.
No worries on the English, entirely understandable. It's the ideas that count!