Because to me designing a piece of software is the analytical work: making estimates, picking candidates for data structures and algorithms, doing back-of-the-envelope calculations, considering trade-offs, maybe making a little prototype in a toy language.

The coding proper can be done in a less vigilant state: it is like laying bricks or folding napkins. The hands know what they are doing. (Exaggerating here, but not too much. God knows I have coded tired or drunk or stoned, and not even my worst work.)

I generally agree that coding can take a lot more planning than writing and the more experienced I get, the more I plan. I also like to occasionally run with the "write one to throw away" method, which is very much like splitting between writing and editing. It's just that the second version is less editing of the original text and more editing the original approach / methodology / process.

I so wish I could code stoned. I've never been able to in any meaningful way. I don't code inebriated anymore, but in my twenties it was preferred. These days I think my brain basically responds to inebriation of any sort as "why are you still working while I'm trying to enjoy myself?".

One of the most complex pieces of code I have ever written, I wrote while traveling home intoxicated on the midnight train.

It was something I had been considering, analyzing, debating and discarding as impossible for several weeks prior to that. Then when it came down to it, not only was I able to implement it, but it worked perfectly for more than 6 years before anyone was able to improve on that design.

I attribute the success to two things: (a) the fact that I had done a lot of analytical work beforehand; (b) the inhibition-lessening effect of alcohol that allowed me to enter the zone and implement the solution without worrying about complexity or other external factors.

Once the core idea worked - and worked it did! - all that was left was to revisit it the next day, sober this time, and fix the remaining issues, documentation and tests.

i hope you checked the code afterwards. i can't code when i am not fully awake. but somw of the best documentation i once wrote after pulling an all-nighter.