@crumbs. ASICs have always been possible, and they always will be possible. Ignoring that doesn't make the network more secure.
The "good miners" making some kind of agreement to use inferior technology (i.e. 1/10th the hashrate @ 10x the cost) doesn't make the network stronger. The attacker will simply bypass that and use the more efficient technology.
I realize ASICs were always possible, but an attack on the network by an ASIC designed *exclusively* for such an attack is a bit irrational, don't you think?
Why not design & build it in the open, fund your efforts with pre-order money, and *then* play with the network? Why Spy vs. Spy when miners will *pay* you to build the silly thing, and fight each other for the right to send you money?
Say at one time the network consisted of $20M in GPUs. Was the network secure? No not against any real threat. An attacker with $20M in funding wouldn't build $20M worth of GPU just because that is what the idiot defenders are using. I mean this isn't some kind of ritualized duel at sunrise. No instead the attacker would just spend $1M on some low end (130nm or older ASICs) and have enough hashing power to 99% attack the network at 5% of the cost.
What "older ASICs"? The attacker would design & manufacture enough '00 tech ASICs just to troll the network with a 51% attack? I'm not even sure if the 1 mil figure makes any sense -- i suspect the investment needed is much higher. What would be the finacial gain? Bitcoin price would *zero out.* Where's the profit? That's one expensive prank.
Now in the future yes an attacker can use ASICs (but they always could) however when the hashrate rises to say 20 PH/s it is going to cost a lot more than $1M to 51% that. ASICs alone don't secure the network but they do prevent an attacker from "cheating" and doing a 51% on the cheap.
You're forgetting that these ASICs are manufactured by ... a manufacturer. Who may mine with them (this is one of sound business models), and, if successful, can easily have an instant 51% attack in *just his warehouse stock.* Sure, there were the GPU manufacturers before, but they had bigger fish to fry. BTW, there is almost no difference in cost between making 10 or 10,000 ASICs -- so, why not?
These miners, as they grow toward obsolescence & their profitability plummets, will get sold at that point to professional miners (who have lowest energy & location costs).
Unsupported and I really doubt that. I don't think that any "pro-miner" wants to manage 50,000 USB Block Eruptors, connected to 6000 USB hubs, and 200 host PCs. No most likely they will be heavily discounted and sold to other hobbyist. The fact that you have a variety of sized hardware from a variety of manufacturers is a good thing. Those looking for max hashpower with minimal overhead/complexity are going to use a manageable number of identical units. Managing 10 TH/s using 20 identical BFL minirigs is a lot easier than doing it with 208 Jalpenos, 3,187 Block Eruptors, a handful of various KNC offerings, etc.
Just how much hobby fun can you have with a Block Erupter? Why would anyone buy, oh, 10 tinker-proof, mine-at-a-loss identical things instead of *one*? Mind you, other than adding a *truly insignificant amount of hashrate to the network,* there's nothing to be done with them. (remember, we're talking about the future, the things are really obsolete)
I, of course, am talking about modular gear, along the lines of Avalon & BFL big guns, stuff that feels at home in racks or could be simply reconfigured to be happy in data centers.