Caucused Mediation Inherently Deceptive?

Take this 2000 article by JAMS neutral and former U.S. Magistrate John W. Cooley, Defining the Ethical Limits of Acceptable Deception in Mediation for a spin.

This article proceeds from the premise that consensual deception is the essence of caucused mediation.

This statement should not come as a shock to the reader when it is considered in the context of the nature and purpose of caucusing. Actually, it is quite rare that caucused mediation, a type of informational game, occurs without the use of deception by the parties, by their lawyers, and/or by the mediator in some form. This is so for several reasons.

First, a basic groundrule of the information system operating in any mediated case in which there is caucusing is that confidential information conveyed to the mediator by any party cannot be disclosed by the mediator to anyone (with narrowly limited exceptions).

This means that:

each party in mediation rarely, if ever, knows whether another party has disclosed confidential information to the mediator; and
if confidential information has been disclosed, the nondisclosing party never knows the specific content of that confidential information and whether and/or to what extent that confidential information has colored or otherwise affected communications coming to the nondisclosing party from the mediator.
In this respect, each party in a mediation is an actual or potential victim of constant deception regarding confidential information -- granted, agreed deception -- but nonetheless deception. This is the central paradox of the caucused mediation process. The parties, and indeed even the mediator, agree to be deceived as a condition of participating in it in order to find a solution that the parties will find "valid" for their purposes.

Lifted entirely from Victoria Pynchon's Settle It Now Negotiation Blog, with thanks. Fascinating, especially in these parts where almost all we see is caucused mediation.
Comment from Geoff Sharp at Mediator blab...blah...:

Diana, I'm interested in your comment that most of what you see in your neck of the woods is caucused mediation. I'm always suspicious of mediators who work in this way.

I believe that usually, it's either laziness or a lack of confidence/competence. The brain surgery of mediation is in joint session - that's where we ply our trade.

Other views?