If its very wet we should be reasonably ok grip-wise from the Diablos, and it will be down to technique/bottle for how fast you can go.
I don't fancy it if it is just damp or drizzly as the first sessions on a damp track last week were a bit hairy. The surface seemed to dry out at different speeds so some corners were ok going in, but then had slippery patches on the way out and the tyres didn't seem too grippy in those conditions.
But hey, why worry, we'll all be in the same boat, maybe literally