the "why" as i understand it is a complex reason that is both difficult to translate A, from japanese to english and B, from a programming perspective to a user's perspective.
it's not a matter of something being added or removed, it's a matter of the architecture of the code itself. for example/comparison, a former limitation was that in order to edit an event, OVERDUB had to be on. similarly, the "why" behind that is a foundation level code thing, beyond my understanding/capability of explanation.
basically, there are other seemingly unrelated bits of how OS2 functions that are apparently dependent the way it is now. i have a couple inferences as to what, but those don't really matter. i am constantly hitting the stop button, scrubbing backwards, hitting play, rerecording, stopping, skipping ahead, playing, stopping, so this change never bothered me.
in my first session with os2, i was more surprised when i couldn't change seqs while recording, but that surprise lasted maybe 2 or 3 times, and then i just figured out another way to do the same thing. my issue here was mainly with long qlink sweeps and pickups - now i just use irregular sequence lengths and qreal position holders.