(ET) Reverse draws a lot of current: Why?

["Christopher Zach" <czach computer org>]

Interesting observation:

While testing out the mower on the E20, I backed up my driveway (somewhat
steep hill, paved) with the mower running. I heard the blades slow down,
looked at the meters and found the power meter pegged (lots of amps) and 
the
voltage meter in the red.

Odd. Took the tractor up the hill in forward (I was in L gear), no problem
with power or batt capacity. When I take the tractor up the hill in D2, the
electronics will sometimes cut off the FW system if current draw is way too
high (no problem there).

Something odd happens to this ET in reverse. I have noticed that the motor
spins a lot faster in reverse than fwd at the same speed setting and gear
with a lot less torque. Also it seems the current draw in reverse (esp when
you go to field weakening speed 1) is insanely high (FW2,3,4 are locked out
in reverse BTW, but one appears to be there since CC works).

I've also noticed if I floor it from a dead stop in fwd, the tractor starts
up (quickly, it doesn't have the electronic delay, only the mechanical one)
and goes to speed. If I am in reverse and floor it from a dead stop, 
current
goes off the scale, and the tractor moves *forward* slowly. Go reverse and
step through the speeds and the tractor goes backwards just fine.

Any idea why?
Chris