note that bookmarks don't float, unlike git branches, so if your pattern is to produce a lot of commits, you'll want something to keep your jj bookmarks pointing to the top of your pile of commits.
this is less of a problem if you're more into the 1 change == 1 commit workflow.
This looks like any other git arcane incantation. If this is a common pattern and jj aims to make things easier, should probably be part of the core commands, no?
It's something that makes a specific workflow easier, a lot of folks that use jj don't necessarily use that workflow.
That doesn't mean it couldn't be a core command someday, but given that the alias works well for people, there's not a ton of reason to make a whole new command. You configure the alias and you're off to the races.
this is less of a problem if you're more into the 1 change == 1 commit workflow.