Protect should be in the first slot, always. Cleric Stance should never be the first. Blizzard II is only useful for FATE's and is general worthless in all content.
Everything you said here is wrong.

Asking if they can have Protect is not being a jerk. It's a perfectly reasonable request.
It is somewhat reasonable, but if you're stopping the run to ask a non-WHM for Protect before maybe... level 30, it does demonstrate your lack of knowledge of how the cross class skills work, and how much you overestimate Protect's contribution in early dungeons.. Not everyone will put it in their first slot, nor should they necessarily.

Easy solution slot it, cast it, switch it out.
This is not what I'd call an "easy solution". For one, I guarantee I would forget to do this before every low level dungeon because *it just doesn't matter*, and two, having to do it twice after entering the dungeon is a lot of ability downtime.