Any way we can really know if the ASIC miners are mining already, or do we just take their word that they'll ship as soon as they physically exist? From the company's perspective shipping without mining a bunch of BTC first is like throwing money away.
ASIC companies don't mind having to ship product without mining with it first. Why? The sooner they ship the sooner difficulty goes up, and the sooner their first ASIC customers return seeking more ASICs to keep profitability up. Selling gear is guaranteed instant profit. Even better when customers prepay and you have money in the bank before shipping. Using the units to mine always carries risk as bitcoin could crater and be worth $1 tomorrow with the company left with a lot of useless gear no one would want.
I may be naive, but aren't we paying for the new ASIC hardware in BTC? How much do you think the ASIC companies are converting to fiat?