Robert Willens (Managing Director, Lehman Brothers, New York) has published Transactions Motivated by Tax Avoidance Can Be Respected, 109 Tax Notes 1341 (Dec. 5, 2005), also available on the Tax Analysts web site as Doc 2005-23462, 2005 TNT 233-25.  Here is the opening:

It sounds inconceivable, but nevertheless it is abundantly clear that some transactions — motivated solely by tax avoidance considerations — will be "given substance" for tax purposes. Those transactions, despite their lineage, will be accorded recognition for tax purposes. While it is difficult to generalize, it seems that when a particular tax outcome is desired, and that outcome depends on the ownership of a specified amount of stock in a corporation as of a certain date, "threshold" transactions undertaken for the sole purpose of either meeting or avoiding that level of ownership will always, if certain conditions are adhered to, be fully recognized. Some examples: