[roryirvine]

But then you have multiple copies of your repo which is inevitably going to end up with a my_project_v2_FINAL_3b/ mess, reminiscent of how people used to manage files before version control.

Not having to deal with all that is exactly what git is for.

[Vinnl]

I'm pretty comfortable with Git, but I've still done this a number of times, and in my experience this situation is very evitable. After I've completed my gnarly process (whether successfully or unsuccessfully), I just delete the folder I don't want to use.