Hi nothernone,
I learn things on every dive, often subtle, sometimes more dramatic. I mostly dive solo, so have no distractions to my own diving. I know my gas consumption and NDL quite accurately, even before the occasional check. I have a really good idea what variables like temperature, current, effort, will have on my dive. I have an innate sense of navigation in my most commonly dived area and have a very good idea of where I am and where I am going most of the time. Occasionally, conditions are on the extreme end, I'm generally, easily able to deal with these deviations from the norm. I've made, at least my share, of mistakes, and have learned from each and every one of them. As a diver, you are always learning, no matter what your dive count and cumulative time underwater.
Good diving, Craig