I haven't played the game to the end in something like five years, and I've forgotten loads. I'm going to wait one more year and then it's fandango time again.
When I first played the game, I had no idea that you could examine items in two ways. Because of that, I've never used the other way in the last two years. There are plenty of new things to be discovered.
The attention to detail in this game never stops to amaze me, especially since you often discover some little piece of description or dialogue that seems completely random, but then later on in the game, you find something else that connects to it, and everything clicks into place. It's perfect.