Using a tag instead of a main branch?

[hjfreyer]

The project I work on doesn't use branches to indicate the current state of "upstream" - it's based on jiri, which tags a commit with JIRI_HEAD whenever one syncs.

Currently, I use a wrapper script that runs jiri update, and then git branch -f main JIRI_HEAD, but:
a) It's slightly annoying that I need to do this extra step, and
b) It's slightly annoying that there's a branch involved at all - I try to work in a "detached HEAD" state at all times, but if I run git prev and land on main, I'll accidentally check out main and then any commits I create will move main away from JIRI_HEAD and I need to do another reset.

As far as I can tell, there's no need for the main branch to actually be a branch - is there a reason I can't use the tag directly?

Or to put it differently: git branchless? More like git branchful amirite?