I believe Dorico does this so that it can be sure that the playing techniques (keyswitches, controller changes, etc.) that it needs to trigger in order to produce the correct result in playback will be synced up with the notes to which they apply.
I believe Dorico does this so that it can be sure that the playing techniques (keyswitches, controller changes, etc.) that it needs to trigger in order to produce the correct result in playback will be synced up with the notes to which they apply.