You're missing OP's point: ASICS don't bring uncertainty, the outcome is *certain.* If you had a money press that prints real money, why would you sell it?
Edit: ASICs are, or are claimed to be, these printing presses. If they make more bitcoins than you pay for them & the juice to run them -- a no-brainer win unless... THE VALUE OF BITCOINS GOES DOWN. That's the only sound reason to sell the printing press And they're being made. And sold.
I think you misunderstood - they create uncertainty in the future of Bitcoin - i.e. will it survive the concentration of mining power that ASICs are being used for?
The real winners of ASICs are the companies that produce and sell them. Anybody mining with ASICs especially those high end ones mentioned will always see a declining return even if Bitcoin remains the same price. It's a losing battle, the more power they add to the network the more difficult if becomes and the less bitcoins they make. This is the reason that ASIC companies simply couldn't produce all their machines and turn them all on to make $$$ - after a couple of days the difficulty would shoot so high that it wouldn't make sense.
That's pretty much my point, but see if this works any better for you:
Premise: Asicminer thinks its rigs, sold to marks at a markup, will still be profitable for the marks.
Conclusion: Asicminer are fools to sell, they will get more bitcoins by mining with their chips themselves, and if the dollar value of each bitcoin remains the same as it is today, they will get a greater profit.
Corollary: Either Asicminer are a bunch of noobs, the other miners will not recoup their investment (in bitcoins), or the last option: the value of bitcoin is expected to decrease, so even if the miners get back their investment in bitcoins, those bitcoins will be worth less. Fail.
By selling now, asic companies have zero interest in longterm stability of the network, zilch.
TL;DR: If it's not profitable for Asicminer to mine with all of their chips, it's certainly unprofitable for anyone else to pay a markup & mine with those same chips.
asicminer is just "shares" of someones' mock stock market printing press NYC;)