Follow-up from "WIP: "Geo: schedule a git repack after initial clone""

The following discussion from !5261 (merged) should be addressed:

• @nick.thomas started a discussion:

  This is all getting a bit... nested. I feel that we should remove the redownload parameter and have two separate methods instead. It's an involved refactor though, so I don't mind leaving it as ~"technical debt"

There is potential for big hairy refactor here, so proceed with caution :-)