I understand you pretty well here - I can sometimes get into this mindset and if I do get in the mindset to try and avoid the Fi problems, I do get perfectionistic about it. Online I do have time to overthink it and edit whatever I write, rechecking a couple of times with this vague feeling in the background about whether it's good enough by now or not. Offline/IRL I either speak/act without thinking or don't speak/act at all, no other options lol. I can't edit myself while speaking/acting and also hard to make myself think up some way of speaking or acting before I actually do it, at least not from the standpoint of politeness and such.
Anyway so that means, the offline version of my PoLR perfectionism is simply me not saying or doing whatever but in the case of actions that is something I can't really force on myself for long because it'd be extremely frustrating. So I really prefer to simply go ahead with acting. I seriously don't like to limit myself for no real reason and tbh even if there's maybe a little -note, pretty vague- reason it's usually not big enough to see it as justified let alone make sense of it... As for just talking, I can hold myself back there easier than with actual actions. I'm alright with not always talking.
Of course the above only applies when I'm actually -even though really vaguely- aware of a possibility of issues. Most of the time I'm not aware at all of the possibility of making a mistake in this area and unless someone lets me know I will never realize that a mistake happened. Well sometimes, probably with the worse kinds of offenses, I do suddenly realize the next day or perhaps weeks later that I've committed some mistake but it's still vague, I do not know what the mistake is exactly or why it is a mistake or how serious/big it is, I just have this generic hunch that "it must be something terrible!!" which I can't really do anything with, as it makes no sense; besides it can't be fixed or I don't care to fix it and so I just shake off the feeling. I find this extreme delay in processing this cognitive aspect really funny...
To sum up the reasons for all that, it all really comes from the fact that I don't ever think about how other people may feel on the inside about something. This is because I don't check for my own feeling attitudes either, I really do not need to have them at all and I just automatically assume that others are like me. If I were to guess at other people's feeling attitudes, there's two problems with that, I have a cognitive aversion to guessing in general and I wouldn't be able to make any realistic guesses anyway and so if I want to pay attention then it's an all or nothing switch as I already described above.
A solution can be using some general norms of politeness but there's 1) too many of them to remember 2) it takes a while to recall and I can start talking or acting before recall starts 3) it's subjective, something may bother someone and then someone else may be totally fine with the same something. That'd be fucking confusing trying to follow all that, to keep it in mind for each person, like I'd really have to be a perfectionist haha.
Another solution for me is having made up my own explicit -and pretty simple- system of what behaviour is fair and reasonable. That includes telling people how I am & telling them they need directly to tell me if they got a problem. That sometimes works surprisingly well though I only think of telling others about that in detail when there's conflict. I noticed some Fi types also manage to figure out over time that I'm just like this and they can accept it. Also just on the most general level, I have the principle that everyone is responsible for their own feelings and reactions as everyone is a free agent with ability to respond/handle whatever another person does/whatever is going on in a situation. So overall the Fi stuff is less of an issue compared to how it used to be.
Interesting because I don't relate to this part. If I want to invite someone out I will just do so without ever wondering if it's appropriate or if it's a friendship that's close enough or what. I can come across as distant too, though, that's when I try to be appropriate by not saying too much and especially not doing the kind of poking that I like :/. If I do start interacting with people socially I will soon become too much for a few people, lol yeah.
Otoh I'm curious, if you were told if someone's indeed supposed to be a close enough friend for you to invite them out, would you be happy to receive such advice and would you be able to believe it, make sense of it, actually use it?
I don't think it would truly help me if I even wondered but as I said I usually don't think about this issue at all. If I do, it's more like in the form of wanting to know if I'm liked, or in the case of certain people, wanting to know if I'm still cared about, etc and I just ask the person directly... and then I don't know what I do with the info, lol, I don't think I really use it for anything...? So other than that, terms like "work friend" don't make a whole lot of sense to me. Why does that sort of category have to exist? Or how on earth is it too invasive to ask someone to hang out? Etc..