First, I'll answer the question directly. No. Using force of any kind to get people to conform is not productive in an environment such as this. Also, I am of the opinion that there is little more that can be done to encourage RP, other than what is being done currently (tutorial, player guideline, this forum). Anymore encouragement and we start bordering on enforcement.
The solution to this problem is not an easy one. PlaneShift is put out there for anyone to download and use. Now let's look at the term "anyone" for a second. Do you realise how many different types of people there are in the world. Of all the millions of people who are able access the game, no two people are the same. So this begs the question, how on earth do you create a game that will be enjoyable to everyone. The answer, you can't. It is literally impossible to cater to everyone's needs.
This then leaves us with a few options. We could open our doors completely and let every j03 s04p in, and stop promoting ourselves as an "RP" game. In my opinion, this would mean that PlaneShift will lose it's uniqueness and the community I've come to know and love would more than likely disappear completely. Our other option is to close our doors a little more, filter new players more and smite those who deliberately obstruct the flow of RP in game. This would certainly improve things for the so called "heavy RPers", but we would introducing so much unnecessary negativity towards other people, not to mention increasing the workload of our already overworked GM and Dev team. I believe the game will become a frustrating experience, with people constantly on the lookout for the RP police.
Our last option is to keep things as they are, at least until the game develops into a state where RP and leveling run a bit more parallel. As a whole, our community is pretty tolerant of new players who do not yet understand RP. Let the heavy RPers RP heavily, Let the levelers level, Let casual RPers RP casually and let GM's smite those who cause trouble. The current system has worked for us so far, why change it?
It all comes down to personal attitude, if you allow your in game experience to be hindered by others, then the fault is your own. The trick, in any community, is to find your place, the place that makes you most comfortable and happy. If you are not happy with where you are at the moment, instead of trying to change the environment to suit yourself. Change yourself (attitude) to suit to the environment.