In small roleplay, I find the idea of separate posting to be more detrimental than slow posters or speed posters. If you have five or less people, just use titanpad and you'll increase interaction tenfold, increase quality, refine the end results and encourage every being together or being part of something instead of individual posting. Not saying to do this all the time or to require the entire group, but it is just exponentially more effective.

In larger groups, it's beneficial to actually find a method to separate out the different kinds of posters until they need to interact. If you have 6+ roleplayers, you're gonna kill a roleplay by forcing them to all be together all the time, so it's just a feat of social and literary engineering to get them segregating in efficient little groups.