It would be a step forward and many 'wrong-doing' users don't know that certain actions on the server are inappropriate. There is an element of self awareness and common sense involved as the player should have a good understanding of what to do in certain circumstances, nevertheless a 'rule book' is needed. Even if it is just a thread created with a tinyurl link which is shared around the iPhone server it would give players an understanding for what is unacceptable. The complication here is that a staff member would have to publish the post as nobody else has the authority to, that's why it is vital an influential staff member reads through this thread.
That cuts to the dire point of why this feature must be implemented. However on another level on the topic of the harshness of the bans, the current staff are entrusted with the responsibility to handle the situation in the right fashion. Through this point it could imply that the much lusted 'rule book' may help clear up any of the staff members queries if they're unsure in a situation.
As every argument has it's positives and negatives, there is the worry that a rule book has something for the offender/victim to refer to while searching for some sort of argument to gain the right of freedom once more. There shouldn't be any problems if both staff and players keep to these 'set in stone' rules, but as anything rules can be twisted and misinterpreted which could lead to further drama and debate.
That should clear up the whole issue but there are underlying reasons which cause this thread not to have a simple resolution. Enough said about the topic.