The Guardian view on Friedrich Merz's grand coalition: gambling on a new centre ground

Some years ago, hundreds of German finance ministry staff dressed in black and formed a giant zero to salute their boss, Wolfgang Schà¤uble, as he left office. It was a tribute to Mr Schà¤uble's extreme fiscal conservatism, which had delivered Germany's first balanced budget in the postwar period. Amid resurgent prosperity in the Angela Merkel years, the so-called black zero - symbolising a constitutional prohibition on public debt - had gradually acquired cult status. As a new administration prepares to take power in Berlin, it seems unlikely that human euro signs will welcome the latest politician to take on Mr…