You, ah, missed the whole discussion that lead into this, about specifically recruiting the women who are passing or failed to pass as knights? Part of the "2nd chance" part of the proposed action. I think it gets the skills without the liabilities (besides slowing expedition slightly, equivalent to other cavalry, and maybe improving speed overall if they can prevent the wagons from being stopped) and it gives us another long-term unit to project power from the Karak with.
There's some subleties to the proposal you are glossing over, hard, and so I find your arguements vastly overstated.