It was one of the devs (Peter Todd maybe) who wrote on reddit that Sidechains are not a solution for scaling. For some time now, I haven't seen them claim that they are. Sidechains are still said to be ways to test all sorts of alternative ideas without endangering Bitcoin itself.
Last I heard, Todd has nothing to do with Blockstream other than he throws rocks at them as is his nature. Philosophically, I like his treechains idea better but I see it as at best impractical and maybe impossible. As I see it, what I had in 2011 called 'subordinate chains' have a wide and diverse set of advantages. You've quasi-listed a few.
As for myself, I have read the Oct/2014 whitepaper with some care, It mentions many examples of things that COULD be Sidechains of bitcoin; but I still don't know what CANNOT be a sidechain.
One fundamental property is that each sidechain is supposed to be designed, implemented, and managed by an independent team. Therefore the bitcoin developers cannot give any assurances that the sidechain will do what it claims to do, or will follow any constraints.
According to the paper, a sidechain can even have its own tokens, not pegged to the bitcoins that were exported to it. I cannot see how the sidechains could help bitcoin scale to hundreds of millions of users -- except by being altcoins independent of bitcoin.
As I see it, the 'chain' part of 'sidechains' would be a bit of a misnomer. I'd imagine all sidecoins to have a chain to use as an interface layer but not necessarily as a back-end. I would hope that it is close to true to say that there is not much which 'cannot' be a sidecoin. I've argued (sort of) to Adam that a token back-end makes more sense for a lot of use-cases than a '(now)classic' chain-based system. Of course I'm limited in what I can 'teach' Dr. Back about...well...almost anything.
As for Blockstream's 'design, implementation, and management', I've seen nothing which indicates that it will differ from any other open-source project and nothing to be threatened by (unless you have a burning need to feel threatened of course.) If that changes, so will my stance toward Blockstream. And, I expect, so will many of those who are currently organized under that tent.
Blockstream either said straight-out or I inferred that that intend to produce an open-source reference implementation for sidechains. In that case, anyone could pick up the ball and run with it.
As for LN, I have not followed it that closely. My impression is that it is subtly different from how I envision sidechains, but very interesting technology which will be valuable to develop and experiment with if nothing else.
The LN is very different from sidechains. It executed payments by means of "bitcoin IOUs" that are guaranteed by actual bitcoins that were locked by users for a predetermined time. While sidechains are too unconstrained, the LN is too constrained.
From all that I know, it has some formidable practical problems, like requiring that users lock in advance all the bitcoins that they intend to spend for the next 6 months into bank-like entities.
I have asked about these problems directly to Adam Back, Luke Jr, and a few other developers, including Joseph Poon, one of the LN inventors. The dialogue always ends at that point.
The thing about LN that really impressed me was the 'slack'. Once in a while I pull the keys out of my pocket and a quarter comes with them and falls in a gutter. That does not stop me from using coins and having pocket change. From an engineering perspective there is a huge amount to be gained by having a little room for error. That the designers were cognizant of this impressed me...although it is rather obvious to anyone who has done systems work.
I'll not speak for the LN developers, but as a general design goal a fraud-proofing perspective, the most critical thing is to
not allow an operator to profit from fraud. This will almost completely evaporate many forms of fraud from even being attempted. A distant second priority would be how long it takes me to get my value back in the event of a failure (which I would expect to be an uncommon event and one I may never see.)
Well, right now, if they control Blockstream, they control the future of Bitcoin...
Considering that most of the Bitcoin 'core developers' who are worth a shit are involved, that would be true with or without the Blockstream umbrella.
The fact that sidechains and Blockstream has you (Stolfi) running scared is one of the best indicators yet that the may live up to the hopes I have for them.
So you don't mind having the bitcoin network literally owned by
one company, which intends to make it unusable for its original purpose and to reuse it as an internal component of their nonsensical project... It makes me very hopeful that bitcoin will collapse -- not under external attacks, as bitcoiners always feared, but from the greed and mistakes of its defenders. It will be fun to watch...
- Open source means that they not only welcome competition but foster it. So down goes the 'one company' BS. Blockstream only need to do it better, and that is highly likely given the makeup of the entity.
- Nothing about sidechains in any way detracts from the ability for individuals to use native Bitcoin except perhaps that they won't be subsidized and will thus have to pay transaction fees proportional to the cost of operating a secure system.
- Given the level of talent who were induced to work on this project, you should think a little bit about who looks like a clown when you label it as 'nonsensical'.
I do sense that you are deeply hopeful that Bitcoin will collapse. Again, I suspect that this is why Blockstream and sidechains bothers you so much.
