Doing randomizer work for a game like Dark Souls III is really interesting, because a core aspect of the Dark Souls design ethos is that parts of the game ought to be missable. It should be possible not just to skip content, but to lock yourself out of it. Missable corners of the game are exciting they create a sense that you never quite know what's going to be around the next corner or what consequence your actions will have, they encourage players to talk to one another and share tips, and they make replaying the game over and over even more worthwhile.
But in a randomizer setting, anything missable is pretty much strictly bad. The exploration motive is a lot lower since rando players usually come in with a strong understanding of the game to begin with, and you can't afford to put anything that's actually necessary to beat the game in a location you can lock yourself out of—that's just inviting soft locks. So every missable corner of the game kinda might as well not exist at all.
For now, my practice is just to mark those locations as not being able to contain progression items and move on with my life. But once I get the first draft of my new DS3 randomizer ready for release, the next big step is to start looking at unwinding the missability entirely by tweaking the game's event code so that quests can't be failed and items can't be lost forever. It'll be a cool adventure, and it'll definitely create a more interesting randomizer, but I also can't help but feel like I'm fighting directly against the designers' intentions.
