The authors note that their explanation is more consistent than any other that has been put forward... but there is enough discrepancy between the countries to ask whether it's coincidental. will be back later... that is, tomorrow morning in good ol' europe.

Rien n'est gratuit en ce bas monde. Tout s'expie, le bien comme le mal, se paie tot ou tard. Le bien c'est beaucoup plus cher, forcement. Celine