Presumably, then, the landing distance for an aircraft without brakes (let's say a Tiger Moth so we've got an example that we all know) won't be similarly affected by the wet surface? And G-ALAN's initial assertion that the water would caused increase drag and stop the aircraft in a shorter distance - would that assertion hold in this case?
(Let's ignore the fact that no one in their right mind would want to fly a Tiger Moth in the rain!)
FFF
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