R5+ RF 70-200 Shooting speed and AF accuracy in servo mode ( quick-moving targets)

Hi!
I am interested in whether the AF accuracy really depends on the shooting speed and in the point of using H+ mode for quick moving subjects ( cars, skiers) etc.
From my experience I get only about 50-70% properly sharp shots when shooting fast-moving objects that approach me like cars with H+. It looks as if the AF motor is not speedy enough to refocus between the shots and around each 2'nd or 3'd shot is to a various extent back focused. It is especially pronounced when using mechanical shutter. (in case of mechanical can it be because of the blackout, which steals the focusing time from the AF? ) The keeper rate does not really depend on the focus mode or scenario.

If I use H mode I have a bigger % of keepers. So for me its is actually not much sense in H+ mode for quick ,moving subjects, as I have pretty much the same number of keepers, just more junk with H+ that eats memory.

Does anyone have the same situation? What is your keeper rate?