That's understandable, though I feel like without a section in the SU for resistances and weaknesses our personas would fail to be treated as if they have any.
Simply put. I didn't put it in the SU because I am not forcing it on anyone. It is ultimately what I feel is an unnecessary addition. Considering we are not running stats nor HP, adding in your own weakness is purely flavor. As I had said before, if you wish to include it, then by all accounts feel free to; I know I'm treating Uncta as if she was weak to Ice and Curse. But the topic of gamification pops up fairly often, as well my own opinions on the role of the GM. While I do stand in favor of some gamification, emulating games one-to-one isn't necessary here.
It leans heavily on my own thoughts on GMing here. Having a forced negative can lead to incentive to cheese around that forced negative. I've been in RPs elsewhere that, in the case of Pokemon, getting around a forced weakness is done by simply typing "He dodges". Having a forced negative also means enforcement of that negative. While I doubt anyone here would try to cheese their way around it (this forum is much better about it than others), I still wouldn't want to have to prowl around people's post like "sorry, you've dodged a little too much there" or "you wrote you got hit with a fire attack, but you weren't as damaged by it as you should be". It's likely an overreaction from me, but the simple side of the philosophy is "more rules = more policing".
Given that information, is using a persona still physically and/or mentally tiring? If it happens to also be physically tiring then wouldn't it eventually defeat the purpose of bringing weapons?
Given the games still block you from doing activities after exploring a dungeon, I'm sticking with "Yes, they are still tiring just as all fighting is". It's not quite to the exhaustion/sickness levels of P3, but the idea still stands.
Now why would you want to still fight with a normal weapon? Same reason you would in game. Using a weapon and fighting in person is tiring, but nowhere near as tiring as using a Persona. If we correlate HP to physical exhaustion and SP to mental exhaustion, using a weapon is such a minuscule amount of effort compared to a Persona that it costs next to nothing. Meanwhile using a spell is mentally exhausting (SP loss) and and ordering your persona to do a physical attack causes a large amount of physical exhaustion (taking off a large chunk of HP).
Of course, we can assume this is all effecting by you being in the Collective Unconscious. This is Persona, drinking a soda will give you more mental focus for doing more spells. The real danger is reaching the point of collapse inside a place where everything wants to kill you. But so long as you don't reach that point, you can just eat some bread, have a few sodas, maybe drink some medicine and then you'll be as ready to fight as the first step into the Other World. Things are entirely based on how society perceives it, it is the Collective
Unconscious. Why would you even bother fighting with a knife when you have a 10 foot murder god behind you?
Society thinks knives are dangerous, so enough cuts and it will kill just like your Persona.
And ultimately we go back to the core of it, I want people to have options. Maybe you want a backup weapon? Your persona isn't as helpful when the thing has you pinned against the wall. Maybe you want to play a rebellious girl with a sledgehammer who lights monsters on fire with a Native-American spider god? Options are fun.