Yeah, of course. Especially for those who are not too blatant with their OOCness — because everything I do in PS is something which I'd consider to be IC, I used to simply do what I do and hope that others would come along.
However, there are also a few people who simply don't talk. Like this one person who asked Gedundk to trade,
ex nihilo, and wouldn't respond to my /pst later. Come on: even if you don't speak the same language as my messages, you can at least acknowledge me.
This is the manner of OOCness which you can easily include in your RP:
Hey, I need to rank up in my Trapeze skill. Can you help me?
The stuff which cannot be included — e.g.
Oh, wow, last night's episode of Wacky Buckaroo Wallaby was outrageous!
— is more problematic. Restricting conversation modes would help there — and also allow NPCs to participate in conversations more easily, — but would also, of course, require all verbatim talk to occur in a chat client operating alongside the RP world proper.
Leastways, that's one way to do it.
