The goal here is to use only LED's through flowering. Let's not add other lights. If we do, there's no way to tell for sure how well LED's work.

At least that's what I would like to see, but then it's your experiment. There has been many flowerings using LED's plus other lights. I have yet to see a flowering using only LED's. I think this is probably because you would have to buy thousands of them to get any kind of yield. Please prove me wrong.