High-Low gears [TANKS]

["erik kump" <ebkump-at-hotmail.com>]

I'd like to pick the brains of those who already have operational tanks or 
have driven one in a battle. I was bored at work yesterday and was 
brainstorming ideas for a drive train. I kept coming back around to the 
notion of having a two or three speed transmission. My thoughts on the 
matter were that having the ability to alter the tank's power vs speed could 
be a real asset on the battlefield, allowing it to adapt itself to various 
terrains. Three speeds would be ideal I think, as having a low 'offroad' 
gear in the 2-3 mph range would give more power for climbing steep slopes 
and obstacles. The middle gear would be the 'cruising' gear, giving around 
4-6 mph and enough power to navigate tall grass and minor bumpy stuff like 
gravel and tire ruts. High gear would be the 'pursuit' gear, giving perhaps 
8-10 mph but only be really suitable for flat grass or paved areas. A 
two-gear system would be a bit easier to build, but as long as I'm talking 
about it, I like the wider flexibility of the three-gear system.
Do you think it would be worth it? Have you ever been in a battle and wished 
you could gear down to move through some really rough terrain that nobody 
else could navigate? Have you ever wished you could kick it up a notch to 
chase down a foe?
I try to follow the KISS rule, and every additional system in a vehicle such 
as this is another opportunity for failure, but I keep coming back to it. 
Can the guys who have 'been there' give me a thumbs up or down as to whether 
or not they feel that this could be an asset? Or even work?
Erik 'quick change' Kump