4r70w torque converter q's
 

Hi all. I normally post in the classics section but figured I would get more answers here on this one. I will be swapping a 4r70w in my '69 when the fmx dies, and I am setting the car up for autocross/road course type of driving. Yes I know manuals are better, but with a 351w I don't trust t5s plus this setup will be considerably cheaper/easier. I will be buying a trans controller and doing the jmod with a ratchet shifter, using switches for OD and TC lockup. Around 350hp/400ft.lbs
I've been able to find answers to most of my q's however since I am not drag racing I have some q's about lockup torque converters.
1) are triple disc converters the only type that can be locked up in WOT Upshifts? What about hard downshifts?
2) can a stock 4r70w be up/downshifted during hard driving with the lockup engaged (assuming TC is up to task)? If no, why?
Just so you know why I'm asking, I want to make the most of a stock 4r70w (other than jmod) being autocrossed. Everything I've read says that if your trans/converter can handle lockup during WOT that it really helps with engine braking and feeling the car react to throttle input. Like you would feel with a manual trans.
My power level should be in the safe range, but I'm obsessing over maximizing this setup for driver feel which automatics typically suck at. There has to be a way to make this work!