I disagree, Negative. Although you're right, that a transmission is vital to the operation...it's not the same as an RCA system. A better analogy: The A/C system. The A/C system is in NO WAY required, but if you choose to remove it from a vehicle, it will be a pain and you will even have to purchase new parts (serpentine belt, etc). Though the A/C system isn't required, alot of people like it. And even those who don't use it usually wouldn't buy a vehicle when it doesn't work.

A_T