Mahler cycles in his centenary year are about as predictable as dead leaves in autumn. But they perhaps belong more in Birmingham than in some other cities. Mahler, after all, was a big factor in making Simon Rattle’s name, and Rattle was a big factor in getting this superb concert-hall built. So the current cycle there, now halfway through, is like a civic statue to the Master: a tribute both ways, honour to the giver and the receiver.