Nice job! Informative, entertaining, and well photo-documented.
I started getting nervous when I did my q6600 because I'd taken off so much metal that I decided to stop. Although it's flat, it doesn't look as good as this because I didn't get all the aluminum off. It's sort of an ugly swirl of the two colors even though it's an uninterrupted mirror finish. How thick is the typical IHS? The last thing I wanted to do was see silicon dust on the paper...
Anywho, this takes millions of strokes due to not putting any pressure on it. That's why it takes so long. It really depends on how untrue the IHS is in the first place. From online discussion and my own experience, 1-3 hours is pretty standard. Since Intel decided to get artistic and made my IHS in a wave-ripple pattern, mine took several hours as well.