I think all this nicely shows what Xara/Magix needs to think about. AD can shift the dashes along using the ‘Phase’ option but that’s not as useful as CD’s corners.

Once you know a program quite well, you can usually find ways round things like corners. Having them built in is mostly a question of convenience, saving time and maybe accuracy - one less thing to have to fiddle about with or accidentally shift out of place, forget to change width, colour etc.

In an alternative universe if I were a developer, in conjunction with consultation with end users, I would take a close look at all the other graphic design applications out there, then attempt to produce something even better.