Why do you think the price would go down if mining wasn't profitable?
A large company requires a lot of revenue to continue operation. Operating using tens or thousands of watts a day will require constant dumping to meet the overhead. A company also has to weight the amount they know they'll get in fiat today versus losing even more money tomorrow. I think the end result with ASICs will be lots of downward pressure, because everyone will want to recoup their investment as quickly as possible and because if the price of Bitcoin collapses the resale value of their hardware also collapses. Hence, best to sell BTC while it's worth something then dump the devices as quickly as possible if the price of BTC appears to be falling. We're already seeing this pretty widespread and ASICs have barely been introduced.
Before there were tens of thousands of smaller scale GPU miners who could easily resell their cards for 80% of their value in 4 months and make more than that 20%. Even more, there was less pressure to sell the BTC in general above your operating cost and the cost of the card because they were random internet dollars that didn't cost a lot to procure (one of my friends just discovered 3.5 BTC the other day he forgot he even mined a year ago). Now with profit and resale value of your device up in the air and the amounts being invested by companies in the millions, I think it's likely we'll see a collapse in BTC value.
Also notice that newer ASICs are already offering a 5-10 fold efficiency improvement over the first gen BFL/Avalon chips (eg Bitfury, which is 0.4 W per GH/s).
If Asics are expensive and use a lot of electricity, miners would want to hold on to their coins until they could at least break even when selling them. If all the miners suddenly stopped selling, the price should go up considerably.
There is no guarantee that the price will go back up, and most of the time you need to try to recoup losses now instead of a year from now if you have a ravenous bunch of investors to cater to.
And if people start realizing it isn't profitable and stop mining... then the difficulty will come back down and mining would be cheaper again for the people who stick with it.
Yes, exactly. This is when I look forward to mining, moreso than right now. I mined throughout 2012 and sold only 25% of it then, 2013 was great.
I'm sleepy, hope this is coherent.