Being a political scientist is not considered an exciting occupation by people who have a life, and  as party conversation topics go, electoral systems are pretty lousy. But with LibDem support somewhere in the high 20s (if the polls are to be believed), normal people start to wonder why 26% of the vote should give them 12% of the seats, while 28% of the vote for Labour would amount to just under 40% of the seats (you can fiddle with the numbers at the wonderful BBC’s election pages).