Oportunity to win without taking first place in every stage (or maybe in any stage at all, remember Gronholm victory in Cyprus 2002) is a part of the sport. Trying to minimize effect of team orders in that way would take out one of the key factors of rallying - importance of surviving.
You can not too much cruise in rally. Someone faster will simply beat you Ofcourse it is a theoretical oportunity that all crews can go on 50 km/h and wait untill someone crashes out, but in this game the speed is required naturally. Without any rules.