While the response provided by Anvaldra explains the logic behind ignoring ruts and ridges, the key factor is still the coverage.
R&R are normally found at THR and by runway exit turnoffs due to snow being compacted by whell loads, thawing and re-freezing. This is when otherwise there is no contaminant - evaporated. Given the physical location it can be agreed that effects on ASDA are negligible.
Quite unlike the original question with coverage above 50% up to 100%. In this particular case, upon visually seeing what it is like, decision to assume contaminated might be prudent, probably selecting COMPACTED SNOW in the TKOF PERF tool.