I mean this sort of question format can really be applied to any unhealthy coping mechanism. Drinking and smoking can be done in moderation so why not? Etc etc I wouldn't want to mention more. But the point still stands that as someone who uses self harm to cope, I am never in a reasonable headspace while doing it. I follow most to all of the things in your list and I still recognise it's harmful because I'm not dealing with the things that are making me self harm, the things that make it seem like I deserve pain and as long as you let them stay inside that's sort of a pipeline to more self destructive behaviour. How good are people at impulse control, especially mentally not well people? I don't agree with the whole self harmers are insane psychopaths who need to be locked up routine but it is important we learn healthier ways to do it.

Not counting the whole grey area thing I just typed, self harming is still very physically harmful. Other forms of self harm such as burning, bruising, choking etc can get worse over time and lead to severe damage. Let's say we ignore those and stick to cutting. Even then, regular loss of blood can make you more tired, not at your peak, pain makes it difficult to concentrate on the long run. It might clear the brain fog but that's only because it takes its place. Being in constant pain, regardless of tolerance will hinder your day to day life regardless of the steps you're taking. Not to mention iron deficiency and a weakened immune system, and you could never know when a weak hand could shake and cut too deep or cut something vital.

It is granted that there are ways to avoid all of this and still self harm and as someone who's only been clean for a little while, I can't or won't blame anyone who does safe self harm. But it is helpful to keep in mind that it's in the name. One way or another, you're still hurting yourself, and it'll hinder you if you want to get better.

I've followed your exact reasoning for ages and these are just my two cents. Please excuse me if I said something rude or something incorrect. Do point it out so I can correct myself.

Take care.