Michael,
Just my experience but I was having trouble with the auto in my V8 VP after 220000 Km and I looked into using the additives in the fluid. I was told they would either fix it or f**k it, and unfortunately in my case it f**ked it. Not long after adding the additives the overrun clutch failed and I lost engine braking. A few months later 4th then 3rd stopped working. As I result I needed a new transmission. Got quoted $2500 for a full rebuild.
On the upside I bought a second T700 as well as some good books and rebuilt my first automatic transmission. It's been in the car now for a few months and is running absolutely magnificently.
CATCH!