2nd gear launch

I'm no transmission guru either but i thing the biggest problem would be heat! And, getting it out of the transmission between rounds.
The converter is making a lot more heat.
Some may say that its no different then a 2 speed auto. but I would bet that even the tallest first gear set up in a two speed is still lower the 2 gear in a 3 speed(727/904)
AKA a clutch that is engaged before the launch has a better chance of staying engaged then one that has to slip into gear or clutch engagement.

I think the 2nt gear clutch is not the concern or issue