That's interesting, the Bambu slicer actually does let you control how much, if at all, you purge during switches - I might try just setting it to 0 and seeing what I end up with..
Ok, then I'm confused. Per Teaching Tech's description, a certain amount of purge is necessary. I've no personal experience with it. https://www.youtube.com/watch?v=p3ZIM3megIU
It is necessary, just not EVERY single time. I remember watching a video that provided a simple and effective method to manually extract the filament. However another user here claims Bambulabs can automate to waste less filament.