Rotorspeed - haven't you been listening?
Look - 'most' pilots scud run especially if they operate within the confines of flying lanes as Peter did and especially if they know that the weather limits are borderline. Most clouds you penetrate during scud running are full of air! One or two are NOT. Guess what -
There was NO pressure to comply with the rules, he had already decided to press on AFTER his principal had told him not to bother. He continued because he was complacent with his performance.
Please try to understand this. He was pushing his luck cloud hopping and ran out of it.