You're mostly correct here, but I think there's one thing worth considering.
Miners are investors. When we see considerable increases in hash rate from new equipment coming online, we should assume that miners are bullish and are not looking to sell anymore than necessary to cover costs. When we see the opposite (downtrending hash rate), we should probably assume that miners are bearish and generally selling inventory rather than holding. This is for the same reason that farmers and metal miners sell futures contracts: to lock in a price before it falls.
I remember watching an interview with a Chinese bloke who was heavily involved in mining, one of the very few interviews I've come across with someone who knows anything about Chinese mining.
He said most of the people he knew of who were mining in China did not understand one single thing about Bitcoin, did not care what they were mining, and were solely concerned with getting as much CNY out of it as quickly as possible in the easiest manner.
Others will of course have a different approach, but trying to second guess their moves through their unknown motivations and situations is a task and a half.