"Processor performance" preference change not taking?

I'm used to keeping my "processor performance" at "reduced" most of the time, unless I'm doing something cpu-intensive like encoding. Lately I've noticed that changing from "reduced" to "highest" (in preferences / energy saver / options) has no affect. (I can tell because my fans don't ramp up as they do when the processor is being taxed.)

Anyone else experience this?