Anyone running a 904 behind a 340?

As was explained to me by Paul Forte of turbo action, if the band is on during transbrake, after the launch, and depending on the valve body design, if the slicks were to hook, slip, and rehook while still in first gear, you would be on the sprag without the band on to help. I purchased a brake that leaves the band on till second gear is pulled. This comes with the complication of band overlap.
That's a bit of a messy mixed up answer..
I think you will find, that's what happens when you use a valve body without rear band apply.
The sprag is not designed to take shock loading, no matter how many rollers you shove in there.
I have seen plenty of race built TF's with stock sprags in them and rear band apply valve bodies.