| Glyn,
In my experience of standard Diablo's they start to slide nice and progressively when they go off. I've had plenty of rear end slides on Diablo's that are just starting to lose that grip they were giving me the lap before ... they just go and it feels like a little twitch but they just keep going and then you realise they are sliding. You just stand the bike up a little more keeping the throttle neutral and it all comes back to you - lovely.
Diablo's offer huge amounts of grip for a standard road tyre and go off progressively and easily. What more can you want for a reasonably high mileage tyre?
HTH
TP | 
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