Of course voting for Libdems in Dover in a general election where only either Tory or Labour can win is a wasted vote anyway..but they wanted to make their mark in support of the promises and pledges Clegg was making.
However when votes are lost like this maybe it does make a case for the AV system.
Just to run with another analogy...the two kids were sitting on a seafront bench both asking for Nick Clegg's ice cream...and I bring them back Coalition Spuds! It wasnt what they wanted.