That has been my experience too. The days when I'm very focused, being extra deliberate and constantly questioning/examining/challenging things, the results are much better. Autopilot days just go through in a daze and the outcome is objectively worse. This has made me much more hands-on and pushed me towards models which are actually not that "clever" like codex at effort=low but fast. Given that I'm doing the meat of the thinking, might as well not be slowed down by the model and lose the flow.