I appreciate that "you took into account a lot more info" then I but take my word that I'm well positioned in the industry and not a home or hobby miner as you are.
There is very little spare hosting capacity out there. No one (other than home miners who are less than 1% of the network) was sitting on machines through February and March. If you weren't profitable then, but are now, you're going to be under water again in 8, maybe 12, weeks, so that is dumb strategy. (ie. a 20% price rise makes you profitable again, so once difficulty catches up with price, very soon, you will be under again. Furthermore, your "carrying costs" of the data centre, like your mortgage/rent/insurance, will ensure this strategy yields less profit as you paid that money while waiting for the price to rise. Furthermore, these 8 to 12 weeks of "back in business" are going to be barely profitable, if at all.)
And from what we all know, chances of those machines being "back in profit" ever again, after surviving retirement once? Little to none.
If my mine was 20% away from being "underwater" I'd be sweating. Not going "Gee, I'm going to plug all this back in when the price goes up". Running a large operation is expensive. As I said, mortgage, rent, insurance, internet, security, employees (you can't just fire everyone and expect them to come back after 6 weeks of unemployment).
Rather than mothball your facility, if you were giving up you'd probably strip it of the electrical (resale on transformers, panels and HVAC is good) and sell the building and land.
Now - your argument is not without merit. If we saw, say, bitcoin return to $500 in the near future. Then yes, everyones going to be opening a mine everywhere, and you will see stored equipment come online. But not at $270. Not enough incentive.
Edit: Also, on your last point about majors maxing out their capacity. Believe me, they're trying. Between fires, equipment failures, bankruptcies, etc. this hasn't been an easy road for most of them. KNC's mine appears to be under water. Bitfury (who are doing fine now) had to shutter a mine in Finland over the winter. We see all of them needing equity investments. If you are making good money, you get debt, not equity. Equity is for companies that need to expand in order to survive.
so if home miners have 1% of the network , 3 to 4 ph out of the network? and 4 ph earns about 41 btc a day. or 1.6 blocks a day.
below is f2pool's payout for july 6th 2015
https://blockchain.info/tx/6a8c32b23b795a8c700e5e46f62151686ac2156ce1c27b8833a7caf0f44df8f0they paid 700btc to 697 accounts
11 th would have paid .1 btc
80% of the payouts where for miners under or close to .1 btc
they are 1/5 of the network . So you 1% of the hash is from home miners means you don't count guys with hash at f2pool.
I think if we merge my ideas with yours we get closer to the truth.
I also think based on my f2pool studies more then 10 % is in home mining not 1% .
I would imagine builder/farms are closer to capacity. then I am saying. But I am sure home miners are at 10% of the network and I know a lot that have idle gear.
so it is a bigger factor then you think. If home miners have 10% of the network and can boost there mining 25% that means they could change 35ph to 45 ph
or a 10ph boost. that is 3%. I still think bitmaintech does not run at 100% capacity at certain times. When they swap s-7's for s-5's which would be now. the hash stays flatter and the power drops. I know you think it is a full power level and for all I know you supervise the swapping out of the gear. so you are certain it is a full power level model for profit.
If so too bad as the gear race will never end if you are correct.