Google is his friend. The cost and energy requirement to drive a wind turbine in extended periods of no wind or in icing conditions are built in to the cost model. It’s negligible in the whole life energy balance and costs; they’re motored very slowly with the blades feathered.Where did you find this interesting tidbit?
Shafts will bow and bearings will brinel (although short shafts with several bearings won't bow in any meaningful way) but this is not an instantaneous process.
@anglo is trying to argue that wind turbines aren’t viable because he’s picked a few isolated days in the spring when there is high pressure over the UK and little wind. Days which are an entirely predictable part of the UKs weather pattern and which can and are managed now.
He’s trying to claim that on a calm, hot summer day turbines are being power rotated. I don’t think he has a clue about the phenomenon of sea and land breezes.