I checked the TAF last night before bed and it was dire. The 07-16 early this morning was better, just showing mainly RA and DZ. By the time I had arrived at work 25 min later it had been amended to 200M +SN again! Verbally we were told we could expect 6-7cm.
The runway was mainly wet through de-icer but when the snow started falling onto it you ended up with the only possible outcome, slush. There is only one thing you can do with slush and that is sweep. This they did and re-opened for a while but with the continuing falling of snow (and it was snow) the same thing happened. Following a report of adverse braking there was no option but to close again for sweeping.
You cannot reliably measure b/a on a wet/slushy runway. If you do this before deciding to sweep you just waste time. They got on with it and swept.
I don't think they did too badly in a no win situation.