Just had this discussion yesterday at quilting. A member of the group brought in her power sharpener for us to try out. Conclusion was it's not really worth it. Some did turn the blade over before chucking it. We decided the best was to stock up on blades when there is a sale and change the dang things when they start to skip or get dull.
I think we wait to change the blade just to surprise ourselves when the new blade cuts so smoothly.
I've just started to carry extra blades to my quilting days and I also have sharps containers for both pins/needles and the blades. Toss when full - labeled.