Satoshi's writing and that particular letter have something in common: Two spaces after a sentence ends. That's the "old" way of writing in the typewriter era where you hit space twice - and you carry over that habit to the PC keyb into the late 80s/90s. You do it too because you are of the "old guard". Younger people, hackers, script-kiddies, well... not only don't they know these things but they won't even spot the difference in order to emulate it. The two spaces, for me, increases the chance that it was original.
Oops, thanks for reminding me. I must watch out and avoid that old habit, before someone figures out my true identity.
The writing style is quite neutral and it feels ok'ish though and in line with what Satoshi has said in the past.
Well, it is a matter of feeling; but I find the tone of that letter very unlike that of previous writings. Too dramatic, almost hysterical. But very much like the tone of Adam and other ardent small-blockians. The personal and nominal attack against Gavin, in particular, was very strange for Satoshi, but very much like Adam's tone at the time.
As for blockstream people doing it, you are saying that they hacked Satoshi accounts back when it happened and then they used them when convenient to promote their agenda? And how would they know that Satoshi wouldn't pull the curtain on them? [ ] It's a very long leap.
The hacker who got hold of Satoshi's email account may have been a smallblockian or Blockstream sympathizer, or may have offered his services to them. (How else would he profit from that "asset"?)
Satoshi is either dead, or is much more worried about hiding his identity than about the fate of bitcoin (which he apparently abandoned in 2010).
That, by the way, is another reason why I assumed that the letter was fake when it came out: if he did not care to intervene in all the previous critical events, why would he come in just to take a side (the wrong one!) in a relatively minor technical dispute?
Especially after Satoshi came out and said he is not Dorian?
If his account was hacked back then, who knows why the hacker posted it. Maybe he was sorry for the old man. Presumably he is a bitconer, and thought that the claim was hurting bitcoin.
By the way, there was another message by "Satoshi" recently, denying that he was Craig Wright -- and then adding "We are all Satoshi". That last part is obviously something that Satoshi would not have written. I can only think that the hacker is aware that everybody is aware that the account has been compromised, and does not care to pretend anymore.