I think he means the dashpot. Its suppose the slow the closing of the throttle to prevent backfiring. I think it has something to do with emissions too.
Oh it was one of those things to me where the explanation made it sound more complicated than it actually is. Its like on a door, to keep it from slamming, buildings put those things on the top to resist it and slow it down so it doesn't slam. I might take mine off, it sticks (only the first time you step on it) and makes a very annoying squeaking noise and it's a workout on my achilles. I lubed it but it didn't help for some reason.
The dashpot is there for a reason; it's to keep the revs up when you shift so the shift will be smoother. It prevents the throttle from dropping instantly to idle. No other reason for it.