Rally Forth is where Servo really shines, since he's immune to the motive drains which otherwise make it a rather useless action.
totally agree with u
i was able to max a sim's 5 skills (starting from level 1-3), non-stop.
basically i put a sim into a room with training equipement, and snapdragons to keep all mood up except energy
and when the energy gets really low, i have my servo couple take turns rally forth in the room to refill the energy of the sim. and then the servo couple played pillow fight to fix each other social and fun