May not be relevant but the Munich Atis today included a warning that the runway might be slippery due to de-icing fluid. In Munich the de-icing is carried out immediately before the runway. A russian A310 coincidentally slipped of the runway close to this point some time ago on take off with asymetric spooling up of the engines. It has never seemed paricularly slippery to me, but then you might only notice it when it is too late and were not expecting it....food for thought.