If a client comes to me and says one of the parts of their application was slow, and I come back to them saying I lowered the number of reductions with zero change in the wall clock time, they'll fire me, and rightly so.
To be nitpicky, wall clock time isn't the same as CPU time or power draw. You can increase efficiency at the same time as you increase wall clock time because they aren't necessarily the same metric.
If a client comes to me and says one of the parts of their application was slow, and I come back to them saying I lowered the number of reductions with zero change in the wall clock time, they'll fire me, and rightly so.