Hey Airhog ! Good on you for trying this. It is interesting that it made as much difference as you colourfully describe. :-)
I thought the other factors of geometry, spring rates, ARB, and damper settings, not to mention the overall weight distribution of the car's layout, may have had such an effect as to make it still understeer.
Shows the value of tweaking a Seven's TPs to tune handling.
There's no such thing as too much bhp per ton !
6SpeedManual