T/R on slippery runways
 

Hi all,

Following the 737 overrun at Midway, and the NTSB reccomendation not to account for the use of T/R on assesing landing distance required on contaminated runways, I was wondering how different operators accesed the subject.
Did your airline change it's procedure for planning landing on contaminated runways?
Does your a/c manufacturer provide data for landing distance required on contaminated runways with or without T/Rs?
Does your company add a company contingency factor to those figures?