What about the cynical party, just out to fact find? How can the 'genuine' other party not be at a disadvantage?

Some parties turn up with a deliberate and cynical expectation of being able to leave again with valuable information about the other party that will give them an advantage back in the litigation.  Most of them realise during the course of the mediation that such 'advantage' is illusory compared to the benefits of settling the case on negotiated terms.

It is very, very rare for a party to be 100% sure of their case.  The Mediator will cause them to look at the weaknesses, even if not admitted at first, and have them ask themselves, and their lawyers, if they are really willing to go to trial notwithstanding those weaknesses.

You don't have to disclose anything that you don't want to, and 'fishing expeditions' go both ways. Remember, though, that the mediator will not allow the transmission of information that is not authorised, and if the mediator considers that one or more parties is not acting in good faith the mediation may be terminated.

Parties need to prepare properly for the Mediation, in the same way as they would for any direct negotiation.  It is important that the parties know their legal 'rights' before they start, so that they have a fair idea of where to compromise and where to remain firm.  In order to help the Mediator test the strength of the other party's case, you must be in a position to point out the strengths and weaknesses of that case as well as your own.