My take on ready positing, carbine or handgun, is that after awhile you find out that you don’t really need or use any kata-style named holds. You are just familiar enough with your hardware and gear that you simply out the gun in a position you need it to be in at that moment while maintaining optimal muzzle direction.
I say “optimal muzzle direction” because frankly there a may be times times you are going to need to sweep things that you would otherwise rather not.
If we are taking about people just getting started, teaching a few basic ready positions can help get them to that point of spatial awareness with a gun. Personally I don’t think I’d be teaching those people anything regarding putting a pistol into close context with their head.
Oh, and for the record, I hosted Hack something like ten years ago. One of the worst classes of my training career. I’m sure things haven’t improved.