I'm running something a lot more codified in beta right now, when my activity is halfway decent enough to justify it. I kind of want to see how it goes, but my thoughts so far is that it more or less depends upon active reffing and a really interested player... and even then, there will still be miscommunications. For my thoughts on uncodified RP's in general, see my thoughts on ASM...
Originally Posted by Fat ASM Nightblade Conclusion Post
WHAT CAN WE LEARN FROM ASM?
This is the big question. I think we can learn that an RP needs...
1) More than one ref. The game died when I was busy and mildly insane when all of the other refs quit.
2) Distinct, hard rules and progression. Organized chaos is fun, but impractical.
3) A clear path and structure that lets anyone ref it with just a little experience and battling skill.
4) P vs P RP's will likely not work. They die if one player goes inactive, and they become way too inactive. See Labyrinth, Inquisition, and ASM for examples of these rules leading to an RP's failure.
Basically, I don't think that a pure RP is actually possible, but I could be wrong.