> even significant fraction of one’s braking needs It's easily practical if you drive in a non-aggressive way. (Its not a race )

I frequently coast up to red lights and stop signs, shedding 25-50% of my miles per hour, but brake wear is greater under heavier loads so doing 25% less breaking is a lot more than 25% savings on wear & tear.

I'm not sure what % is a "significant" threshold for you, but >25% is definitely significant to me.