What I find useful about going deep is not usually what I find at the bottom. It's the tools that I employed on the way that prove useful later. And that's not

What I find useful about going deep is not usually what I find at the bottom. It's the tools that I employed on the way that prove useful later. And that's not only if I'm the first to invent them! Even if they are a well-known pattern: I have now experienced them in ways that instruction cannot provide.