I didn't go to Google but I can relate to your story. Having reached CS courses after tens of thousands of hours programming was very enlightening. Indeed, the CS course layed down all my hands-on knowledge upon a very nice theoretical foundation. I clearly remember saying to myself "ahhh, all that what I've done so far, now i really get it". I had that feeling when studying algorithm performance (with math proofs) and when studying the Scheme programming language (with all the fun stuff : call/cc, tunks, curification, CPS, immutability, pure function, lazy evaluation,...) This + my hands-on knowledge made me a very enlightened dev :-)

I had a much easier time in theory than the other students as well, and ended up being the only non-graduate level student in Quantum Computing, and only CS major in another, Combinatorics. I think a big part of it was that I had a strong maths background, graduating as I did from a Math/Sciences magnet school.