I don't really like the idea of forcing it for several reasons:
1. Parsing text is time consuming and the MOO is single threaded.
It's easy to say 'capitalize the first letter' and 'add a period at the end'. But what does that actually mean? When do we add a period at the end? What if it should be an ! instead? Or a ? instead? Would we only do it if there is no punctuation at the end of a string of text? It would require multiple checks. And while those checks are happening, nothing else is happening (even if it only takes a few micro seconds).
2. What if you intended it? Stylistic? In the moment?
cm I think I'm being followed, and the motherfucker looks like they are about to shoo
Just an example, but I find it might reduce the ability to creatively express yourself. We aren't harping on this as staff to get in the way of creativity, we're harping on it to reduce the immersion breaking aspect of someone rarely capitalizing the start of a sentence, or rarely adding punctuation.
Why? Because we all read a lot and when we see something that our eyes don't expect it can be immersion breaking.
At the same time, seeing something you don't expect can be immersion increasing if done right. I've seen people do really need things with the SIC. I don't know if I want to enforce conformity as the default.
3. SIC is a good canary in the coal mine
We don't -need- to enforce this. And it isn't just the SIC. The SIC is the canary. We see people doing it there and we can assume it is happening elsewhere. Getting a reminder about the SIC can push people to do better elsewhere.
Historically, I'm a terrible speller and grammarian (that's a word right?), but in my 20+ years on Sindome I've got better at spelling, punctuation, sentence structure, etc, both by seeing -others- do it correct, and having people give me constructive corrections at opportune times.