Since he didn't blame the mailer daemon...

[sunnyskywalker]

Prisoner of Azkaban does a good impression of being one of the best-constructed books of the series, as long as you are willing to smile and nod at time-travel shenanigans (which you pretty much have to in any book where time travel appears). But these gaping chasms keep opening up every time I poke at it. For example, Sirius and the mail

Comments

[with_rainfall]

I think this is another example of Rowling’s Peter Pan Syndrome. Characters must hold feverishly to the attachments of their past and become entirely unreasonable, even go to extraordinary lengths, to “right wrongs” (see also: Snily Insta-love, Voldie’s refusal to send a couple of hired goons to kill Harry and co). As soon as he gets wind of Peter, it seems, Sirius gets Revenge Fever and wants to track him down and kill him with his bare hands.

I actually don’t find this all that implausible - not compared to Rowling’s other characterisation, anyway. As a very slight qualifier, I can see why Sirius might have had more cause than most. Azkaban is built/conceived along the old style of the Victorian ‘insane asylum’: not exactly the sort of place that leaves you much mental space to find God and work off your sentence in the prison kitchen. I assume he had twelve years of mental and physical atrophy because the Dementors would’ve kept him subdued. Under those circumstances I’d probably want to kill someone as well.

Again, as someone else said, this is along the lines of his actions in OOTP later on. I don’t see him sitting around, meditating on the most logical course of action like a monk and deciding he’s happy with having Dumbledore kill Peter quietly.

[sunnyskywalker]

I think it's the timeline that makes it weird. If it was only, say, a week or two between his escape and the Shrieking Shack showdown, no problem. But a year? It really didn't occur to him once during all that time? He never once thought, "Hey, I bet Moony could help! He'll want revenge too once he reads the letter I'll get Crookshanks to send for me!"

Well, the timeline and the broom thing. He didn't order just any broom, but one that wasn't even available to the general public yet during Harry's weeks in Diagon Alley. Sirius had to research broom developments somehow. So he can study broom release news and specs and then plot how to order one via cat. Surely taking five minutes to consider whether he could also drop a few lines to one of his two possible allies at Hogwarts doesn't involve more sitting around and contemplating than that? The very act of sending one letter might give him the idea to impulsively send a second letter--no heavy pondering required, just, "Hang on, Crookshanks, give me two minutes and I'll have another one for you to drop off."