With what you've done over the past couple of decades (I assume you're the guy that has written one of the first C++ compilers and invented D), would it not have been better for you to take more classes on compiler design or other computer science/computer engineering related courses? Did jet engine analysis (I assume you're a mechE) ever help you once you found your niche?

Btw...you've seemed to accomplish far more (technically speaking) in your life than me :), so I'm genuinely asking and not trying to lecture you.

Edit: I think pretty much all knowledge I've learned has had some use, but surely the applicability would've been higher for you with more computer hardware, compiler, and algorithms related coursework?