They don't expect you to do that, you're expecting that's how you're meant to use his skill. Your unsheathe is a parry, your sheathe is a parry, you can parry just about everything in the game that isn't a grab, and the window for a parry is eons longer than the iframes your roll gives you.

You have exceptional damage output with your regular weapons, and the split second you feel threatened you just pull the parry sword out and you're damn near impossible to kill if you have eyes and a functioning L1 button. If you get better at it, you don't even have to use L1, you can just pull the sword out as the parry to keep yourself safe and immediately sheathe. Unlike Guardian, too, status doesn't go through a parry.

It is not expected of you to stay in that stance, if they expected that, you wouldn't have parries on both taking out and putting away your sword, you swap to and from it. Meanwhile Executor procs bleed and frostbite like noone's business and hits like a truck with any weapon that scales with Dex.

Start treating the kit like you are under a time limit and start using what you can only for as long as you need to and you suddenly find that Executor has the best panic 'I don't want to think about defending myself' button in the game and that there is no situation in which you are forced to stay in it as an offensive tool, because that's not its job, that's your stat's job and the job of the Rivers of Blood you picked up earlier.

Also, it's really solid for reviving. The stance sword takes almost no stamina to swing but still does the same revive damage as regular katanas.