Lee A. Sheppard has published Shelter Penalties: Or Else What? Part 3, also available on the Tax Analysts web site as Doc 2005-3055, 2005 TNT 30-5. Here is part of the introduction:

At the ABA Section of Taxation meeting in San Diego on January 22, the authors of Circular 230 showed up at the Standards of Tax Practice Committee to take questions about it. Other officials talked about it at other committees. While their responses were not always responsive, they do shed some light on the application of this regulation to practitioners with business clients. Plus there was a hypothetical that did not involve college savings accounts. This article is in question-and-answer format.