How do you Handle the Self-Represented Litigant in Mediation?

This week, I had two hearings with unrepresented Plaintiffs.  These can be doubly vexing when the Lawyer representing the Defendant attempts to bully the Plaintiff by his/her superior knowledge of the process and the law.  Just as on the playground, I find that bullies do not usually win out in life, though they can certainly inflict some pain at the moment.  When these challenges come, I summon up as much emotional maturity as possible and make sure to be extra-deferential to the Plaintiff.  In other words, without taking the side of the "victim", the mediator or arbitrator can add some extra formalities to the process to ensure that the unrepresented litigant is afforded due process and that all of the rights he has are being fully asserted.
In one case, I was confronted by 48 witnesses who had been subpoenaed for an arbitration by an unrepresented Plaintiff.  The lawyer for the employer cried foul and asked that I exclude all of these witnesses as duplicative and unnecessary.  That was a bully tactic and backfired on her.  Instead, I spent another hour going through each one's proposed testimony before limiting the Plaintiff to one witness per category (for a total of 5).

Beware the Bully Lawyer in an attempt to Mediate a Litigated Dispute

Litigators know that some of the most dangerous and challenging cases can be those brought by a self-represented litigant who wants to avenge his wrongdoers in ways that may go well beyond the realm of the law.  But I say "bully beware":  the reason these are so dangerous is because mediators, arbitrators and even Judges will generally be extra deferential to the pro se litigant.
How do you handle negotiation or litigation against someone who is self-represented?