If price depends on the hashrate then there should be a lot of people knows where the price is going and a lot of people do not lost their investments due to the unpredictable price movement. I really do hope its just that easy to predict the btc price.
If it does then a lot people will be able to predict the price accurately, so it means that bitcoin price isn't unpredictable if its because of the hashrate. Bitcoin price is due to many factors, may it include the hash rate in mining but it is not the basis of the price, I think that it was just a coincidence. I know a lot of people are trying to determine what really is the reason of the price movements but always remember that bitcoin isn't as easy as what most people think and there are other factors that can affect the price.