I would agree with Wallace, except that an alteration of the electoral system would:
1) be an admission that the reforms of 1993-94 were mistaken, which would then cast doubt on further reforms, and
2) have to be passed by the existing dysfunctional, self-serving Diet.
Considering that the majority party in the incipient, intensely unpopular House of Representatives will owe its majority to the current system, the likelihood of that party championing a reform of that system is nil.
There is an easier way to fix the system, one that would avoid any monkeying around with the mechanics and require no legislation. If the current system cannot accommodate a number of mutually antagonistic parties, then dump the antagonism.
Let us imagine, for a moment, the anti-Your Party (Link - facetious), a party publishing a manifesto proposing a host of incremental and rational changes and a campaign pitch something like:
"Our manifesto contains the list of items we believe in. However, our government and social systems are based on compromise. We will therefore work with any party as long the overall policy framework is sound."The image strategy of the Democratic Party of Japan hews closest to that of this model party. However, the DPJ clings to the convention of emphasizing the differences between itself and its main rivals, blasting them with a hailstorm of derision.
The results are ignobility and incoherence:
"Vote for the DPJ, the moderate and compassionate party--because you don't want to vote for any of those idiot loser parties we despise."Since the DPJ has not demonstrated an understanding that the above is a huge turnoff, they really cannot blame Heaven for their prophesied demise. (Link)
Later - It should be noted that at the November 30 joint appearance of the party leaders at the National Press Club, when the leaders were asked to write down on their pieces of posterboard the party they would be willing to ally with after the election, DPJ Leader Noda Yoshihiko did write, after "#1 - the Peoples New Party" two more slots, each followed by a question mark --indicating that the DPJ was open to working with parties other than its electoral ally.