I imagine the pilot of Ryan's 737 would have appreciated some guidance at PIK the other week?
Interesting example to quote Capt H seen as I distinctly recall seeing the EGPK Snowtam that morning with braking action figures on it and thinking that they seemed inappropriate. Besides the aircraft came off the taxiway not the Runway.
What needs to be emphasised here is that in conditions of wet snow or slush it is not the braking action which is being reported as being unreliable, it is the numerical value that the mu-meter is giving that is unreliable. Therefore it would be wholly inappropriate for ops or ATC to pass this to aircraft. Far better to get a recent Pirep.