https://www.aa1car.com/library/plateau_finish.htm Scott Gabrielson, a ring engineer with Federal-Mogul, says he is very much in favor of plateau finishing because that is what a ring does to the bore finish when it breaks it in. "The closer we can get the bore to what the ring likes to run on, the less the ring will wear during break-in and the longer the rings will last."
Gabrielson says plateau finishing should be at least a two-step process: a rough honing step followed by a smooth finishing step.
"We are getting close to recommending one bore finish for all types of rings. All our plasma-moly and chrome rings are lapped at the factory so the rings themselves do not need to be broken-in to get them to seal. We recommend honing the cylinders with a #280 grit stone, then touching them with #400 grit stone or an abrasive nylon brush honing tool to plateau the surface."