i actually just had a long thread at t-nation about this with a few people. a lot of them felt that it would be better to do ramping sets for an exercise to 1-2 max sets (maybe 1 hard, 1 complete max of the given rep range) than to do 3 sets of the same weight.
this is it if your interested,
http://www.t-nation.com/tmagnum/readTopic.do?id=2288223&pageNo=0 it starts off just talking about progression but in the 3rd/4th pages it talks about exactly what you mentioned