Up until that line I agreed with everything you said. But hashrate is no indicator of sentiment. Its a delayed indicator of price.
When price fell to the point where even at 4.6c/kwhr it was stupid to mine but hash rate did not fall I knew one thing -- 80% of the people who got into mining bitcoins in June are still mining, which means they are BULLISH. They expect prices to go up, not down. If they expected further down movement they'd shut off their machines and sell cards on ebay.
So when I saw price declining for months but hash rate mostly unchanged I knew there was lots and lots of downside to go. Even at $6 it looked like we got nothing but bulls, so I was convinced the worst is not over.
Ignoring transaction fees for now, its simple, if price goes down, hashrate goes down and vice versa.
Except that hash rate did NOT go down appreciably over the months since we were at $15. Hence it's a valid indicator of broad sentiment (bullish) in an obviously down trending market. People were talking bull, producing, but NOT buying.
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