I once did a scan over our entire code base for []{} vs /=?+, and it came out so close to even as to make no difference. Depending on your language mix, your mileage will vary, but this argument has less general power than people suppose. Dvorak is not terrible for writing code. This is to a large degree because none of /=?+[]{} are in the home row under any layout anyhow. You do lose semicolon under your pinky, but how many QWERTY users are truly touch typing anyhow?