A pulse-and-glide gauge of some sort would be very cool. Hit the "start cycle" button as you start the glide. Coast down to your minimum speed, then bump-start and accelerate back up to your initial speed. Have it calculate the MPG over the duration of one glide / pulse cycle, to give instant feedback. This would be better than the instantaneous display, which would just show infinite mpg on the glide then low MPG on the pulse.
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