(It takes about a second to shift into Overdrive and I think you have to get off the gas a little. On a 0-60 run in 6 seconds, where is the time to shift the overdrive box?)

Wrong! I have a GV behind a 511 stroker. The shift to OD is instant and you do not need to get off the gas a little, keep it to the floor.

(BTW, the internal workings of the GV look very similar to innards of a TorqueFlite, a planetary gear system with a multidisc clutch. The pressure for the clutch is provided by a pump in the casing.)

Yes it is a planetary gear. The clutch isn't multi-disc, it's a cone clutch. Correct the GV has its own internal pump and sump. It's a single piston pump, about 3/8 di.a.

I'm not trying to be a smart a$$, but have you ever driven a car or truck with a GV installed? Have you ever actually opened one up and looked inside?

As far as the split shift goes it's not practical. Since I have a manual reverse valve body I drive mine like a four speed. 1, 2, 3, OD. If I'm getting on it hard, it's 1, 2, OD, 3. I disabled the GV auto feature and manually select OD. The only draw back to disabling the GV auto feature is you have to remember to deselect OD every time you stop.