That's pretty interesting. I've just read something about Metzelers tyres. In order for the tyres not to rip into pieces the same tyre has to be mounted in different directions for front and rear wheels because at the front the main stress comes from braking, at the rear wheels the main stress is acceleration.
I know a bike is usually not something you'll choose to go by in the rain but even for an unexpected weather change I wouldn't risk riding those rubbers. You don't have to be a rocket scientist to figure out they won't drain the tyre but instead 'collect' it thus forcing aquaplaning at low speeds.