how would preferential voting dull political debate?  

It won't solve every ill in any electoral system.  But there is no
debating its superiority to a two-round runoff.

Mark E. Rush
Professor of Politics
Washington and Lee University
Lexington, VA  24450
http://home.wlu.edu/~rushm
(540) 458-8904
(540) 458-8639 (fax)