Time-stretching midi passages (time warp)

Been covered I know before - https://www.steinberg.net/forums/viewtopic.php?t=154204#p828103

but no real answers - probably not possible…

Within a midi region if I’ve played in a bunch of notes that I want (as a group) to time-stretch - ie: change the tempo - is there a way to do that, without affecting all the other notes around the passage?
other than copying and pasting into a new region and messing about with time-stretch on the piano-roll and then gluing back together?

Example: OK so I’ve played in a 17-note duplet in a cadenza (with the left hand playing as well with no click track). The duplet is messy and I want to tidy up the timing. It doesn’t fit the tempo of the track - so I want to rubberband the passage - timestretch so it fits the grid - then quantize to my preference, and then timestretch/squeeze back again so the overall duplet fits the speed of the piece.

Another very common example is harp gliss. The harp gliss always needs some editing for the scale/harmony and velocity and currently the only way I can make the gliss flow smoothly is to manually move notes around - but again if time-stretch was possible then I’d be able to quantize the run without it being mechanically locked to the project tempo.

All other useful time-stretching (audio and midi) is covered well in C10 - but this one seems to be a serious omission, unless there is a feature that I’ve missed…?