To anyones knowlege, has a transmission ever been designed and tested that is composed ONLY of multiple lockup torque converters (2-3) in series?  If the unit closest to the engine had the highest stall speed, the unit at the end had the lowest stall speed, and the lockup progressed from front to back as speed increased, the transmission could accomodate a very wide speed range and still have a positive mechanical 1:1 ratio when totally locked.  It seems that this could potentially offer interesting characteristics and very high (~8:1) torque multiplication at low speeds.

I realize that this setup would undoubtedly have a lower efficiency then a conventional manual or automatic transmission, and would probably have a very large rotating inertia.  But, there might be some specialized offroad applications that it made sense for.