And here is a good example where Myrrus can be used. Enemy drains AF at battle start? She gives it back. You don't have an actual blunt team? No problem, just let Myrus give you the sea of stars stance.

Now of course you could use a blunt stance grasta and slot someone else into her slot, or let Nilya get you a crystal stance that would also work for AF gain purposes provided you hit the blunt weakness. But that's just her problem.
This pledge was definitely quite obvious who it was targeted at though.