I keep mine at max all the time and use the throttle to control my speed, only using brakes when I absolutely have to, or at the very final few feet of a stop so the bike is actually stationary stopped and not walking /creeping the last 10 feet of stopping.
At very best,the amount of power you will regain, is pretty much, what you put in at your last acceleration. So on the highway when you are at a fairly steady speed, it won't do much for you but if you are in a bunch of stop and go traffic, THEN it can be a real help, because, instead of all those starts being burned up in the brakes, you are getting some of them back,for the next go.
Learn how to throttle it for gentle, more, max, and don't just dump the throttle every time you have to slow down. Slow even steady movements both on brakes and throttle make you a safer rider. This goes for racing too. trail braking into a corner at 135, coming down to about 90 before the lean in, using trail braking only, (ie your hard regen) it's an experience and a nice one too, easy transition, good lean and you are always loaded up on the tires and as soon as you are pointing the right direction, ready to twist the throttle again. Grabbing brakes, straightens you up, bye bye lean angle and turning / maneuverability. It's helpful in shitty weather too, because pretty much ANY decent braking on the front tire, if that starts to slide, yah, buh bye.
Aaron