I mean getting a Authenticode Certificate from a well known CA (eg. [2]) and use it to sign the executables. Microsoft does only provide the root keys, which are trusted by default (Microsoft also makes the OS, this whole procedure is used on, so the
users, who do use Armory on Windows, do trust Microsoft anyways.) The private key for the code signing certificate can be stored in the same way as Armory's GPG key, so it's not owned by the NSA. (And actually, it's not the NSA I fear in this use case, but regular hackers.) Social Engineering is a concern only, if you don't check the metadata in the executable.
[2]
https://www.thawte.com/code-signing/content-signing-certificates/microsoft-authenticode/index.htmlIf you use CA and not M$ Certs, its even more horrible and has more attack vectors.
I think there is a slight misunderstanding regarding the use case here. The proposal to have armory executables signed with Authenticode is by no means a magic bullet to make Armory bullet proof against any attack on Microsoft OSs. And in that regard, GPG also has its weaknesses. Maybe less than Authenticode, but by no means is it a bullet proof solution. However, checking the GPG-Signatures on Windows comes with quite annoying usability. With Authenticode this could be made
much simpler and IMO usability is a main pillar of security (that's the reason we use Armory in the first place). So even if Authenticode has its weaknesses, it's still better than no check of the executable at all. And it eventually will happen (has already happened?), that a clueless windows user will use a malicious Armory executable, because he is to lazy to run through the GPG nightmare.
At this point one could argue, that it's GPG's fault, that its usabilty on windows is bad. One could argue, that one should not use windows at all. But that's not the point. The point is, that IMO the usability advantages of Authenticode outweigh its potential security issues by far. Additionally there is no security hole created by having an executable Authenticode signed. The GPG signatures would still work.