Ok generally speaking.. when a multipool joins in.. price starts to collapse till its out of profitability range.. and sometimes even drops below stable price..
Take for example... if a coin has a stable price of 20 satoshi. That will generally keep it in the average profitability zone.. on the other hand when price hits 30 it will be considered the most profitable coin to mine. Under normal circumstances this would just mean a lot of miners will mine our coin and sell it either for immediate profit or keep it in hopes that prices will rise earlier. These options dont exist for multipools as they need to liquidate the coins immediately for btc so that they can make the payout to their miners. Which means that the market will immediately be flooded without the maximum amount of coins in the shortest period of time.. Thank you cryptsy "auto-sell" option... for reference sake multipools like Hashcows and Middlecoin have hashrates that can be measured in the GH/s.
Now the difficulty retarget might keep out the multipools and then again it might not..multipools only mine a coin as long as its profitable. so 1 minutes mining a coin wont matter much in the scale of things.. ive seen hashcows mine wdc for 3 minutes.. before jumping to doge, for them its about the here and now.. not the what happens next..
Anyway, the point to my post is not to spread FUD but to give our generally young(in crypto trading) community a way to understand why the market moves the way it does.. as opposed to me saying it would never happen.. i'd rather say it might happen and here's the general idea of what are the results of such a situation.. it sucks to get caught up in a panic sell.. and a sudden drop in price from usually brings some nut into the thread screaming "Coin is dead"
