Derailed

To Paya Lebar, 14 km. Back to the master craftsman, to see whether my rear derailleur just needs a scrubbing or replacing. While I've lubed the cable (with lithium grease, no less, bought from another shop) and it feels good, it's still not perfect. It's got to work like clockwork (though not sound like one) when I need it most. Good is just not good enough! I leave it there as it needs to be "warded".