[yjftsjthsd-h]

That's either wrong, or right in a way that requires playing with definitions until it's meaningless. Take the traditional example, sorting algorithms; they all do the same thing, but at wildly varying speeds. The only way to claim that some do less is to claim that they use fewer instructions (loosely speaking; pretend that CPU operations are constant time and nothing else matters), at which point you're right but claiming a meaningless tautology. Removing work is a strategy for optimization (sometimes a good one!), but it's not the end-all be-all.