Does architecture explain our problem with coalitions?

A more representative House?In yesterday's paper there was a report of a poll saying that in the face of another no-overall-majority election, over 60% of respondents would prefer a proportional representation system. (Where were they when we voted on it?)

Yet many European countries manage quite happily with coalition after coalition. Why do we find them so difficult to deal with? My suspicion is it's a matter of architecture. Specifically, the psychological impact of the layout of the House of Commons.

Most parliaments are laid out in a curve, but by putting the two biggest parties directly facing each other, there is a requirement that we don't consider what would arguably be the only coalition that could genuinely argue that it had popular support - a Conservative/Labour coalition.

I know at this point supporters of both parties are probably falling to the floor and frothing at the mouth, but in many respects the parties aren't hugely distant, and a compromise between the two would ensure that we got through the maximum number of policies that had public support. Of course the negotiations would be painful - but politicians have to do something for their wages.

Whether or not it makes sense, I suspect we don't consider such a coalition - I haven't even heard it mentioned as a possibility - because of the seating plan of the House. And that isn't really a good enough reason.