Running 12V+ thru the Brake switch does help if you have to stop quickly when in 4th gear. Otherwise the TCC doesn't disengage until the Trans downshifts out of 4th. It would be like slamming on the Brakes & not pushing in the Clutch with a Manual Trans.
Newer 700R4s have more Pr
. switches & will Lockup in 2nd, 3rd & 4th if the internal wiring isn't changed.