Most jobs tend to have at least a couple of days, towards the end, that feel like you have just entered the 'Twilight zone'. The work gets more and more intense as the deadline gets closer and then... comes the rendering. The day or days where you are just rendering all of the separate elements to be comped. You go from a 100% to just staring at a progress bar that moves very slowly.
That is when the doodling starts, while you wait for the ping at the end of another render. The drawings always seem to have a particular quality that I can never seem to replicate on normal days. Exaustion mixed with a touch of boredom channeled through a directionless demented pencil.
Here are some examples from one of my last jobs.