Admittedly, I stopped before then when I saw the poor mathematics rendering. For some reason unbeknownst to me, the equations appear cramped and difficult to read.
I'm pretty sure I know the guy that wrote this (seriously, how many physicists named Alex Alaniz are there?), and he can't have LaTeX on his work computer because of some really dumb rules. So I don't blame him for it being an exported Word document because a LaTeX version would have meant doing this all at home instead of his spare time at work.
What do you mean, a dead user? I was just quoting from the document, as an example of writing some might find obnoxious. Personally I find it rather entertaining.
No worries. This happens when you 'double post' a comment (usually because HN dies in mid submission) and then delete the original. The duplicate then stays grayed out making people think that your account has been hellbanned.