[nopurpose]

update-refs works only in a narrow case when every branch starts form the tip of a previous. Your helper might still be useful if it properly "replants" whole tree keeping its structure.

[duskdozer]

No, as far as I can tell, it's basically just doing update-refs. But in my defense, I just found out by looking for the option that for some reason my git manpages are from an old version before it was introduced

[WorldMaker]

Though at that point it may be easier to rewrite your helper to manage rebase's interactive scripts.