Ya but of it's safe for wet should also be safe for dry. Like I said just use the lower of the two for both.
This kind of compromise makes me lose respect for aviation. I accept the commercial considerations but then just chose one and run with it. 15' for both. Imagine an accidental because of a wet runway and lower screen height. Imagine answering grieving families of victims and saying, well if the runway was dry....Bad luck for the rain.