Awesome links, I'll have to browse through them when I get a chance. Honestly, I think I've only read a handful of satoshi's posts on bitcointalk and that's about it.
He needn't have written anything about taxation, because he couldn't have known how governments would treat bitcoin, i.e., as an investment or as a currency. It's a global thing, after all and each government can treat it however they like and the tax consequences would be different all throughout the world. Satoshi did a momentous thing in creating bitcoin, and that's enough. Why would he bother to speculate about tax? I would imagine he'd thought about it, and he probably considered the probability of tax evasion, but hey....the man created bitcoin.
The whole point of Bitcoin is to be a payment system beyond governments' control. I would be very surprised if Satoshi was spending his precious time contemplating on how governments could profit from it.
Who knows. I've always thought Satoshi isn't one man, but a government operation. That's my tin foil hat talking, which I don't usually wear. I've always thought it was extremely convenient that bitcoin was created right at the time when it looked like banks might fail completely due to the housing crisis of 2008.