I agree. But Blair thinks the centre lies somewhere over to the right, whereas it seems to me that Labour needs to put considerable policy difference between itself and the Tories, which would entail moving far to the left, where they haven't been for some time. Being the only practically centrist political party is what got the LDs, despite all their handicaps, so many votes in 2005 and 2010; now they've given that up and look what happened to them.

Absolutely. I mean, it isn't just Scottish nationalists who made the SNP landslide happen; they had a clear message of being against pretty much everything the Tories stand for. When faced with bad choices and worse, people don't bother with change, but when offered a choice that seems 'good', they take it. (Except, apparently, in Wales. :p)