What do you do when you're exhausted, your brain is fuzzy, and you just plain have to meet a hard deadline in a few days? You have obligations to your team and your company and yourself that just can't put off.
It's all well and good to say you'll take a week off once the deadline is met, but how do you keep your brain operative and your mind focused enough to read and write code for those intervening 3 days when you can barely read a sentence of plain English text without having to go back over it 3 times to extract any meaning?