Guanaco asked in a previous comment how I remember the details of my lesson. Since any answer I could come up with was too big to fit well as a comment, I thought I'd answer the question here.
I think my ability to remember so many details and then to write them down in a somewhat organized fashion is a useful side effect of my medical training. That is to say, it is a skill I developed through practice. As a medical student, I learned to take a detailed history and perform a physical exam on a patient, then in somewhere from immediately to 24 hours later organize the information in a standard format, and present it to a senior physician for the dual purpose of taking care of the patient and receiving a critique of my own process.
These are the factors I think important in producing a useful synopsis of a cello lesson:
(1) During the lesson, pay attention to the teacher. No kidding! That means listen and observe without fiddling or trying things out until the teacher has made his/her point. I make mental notes of what I am doing as I then try it, with the idea always in mind that I will want to record it later.
(2) Begin reviewing the lesson material immediately upon departing. I run through the lesson mentally as often as there is enough time during the drive home. Details start falling out of short-term memory even before the end of the lesson. This slows the decay, and results in more remembered details when you finally get to the keyboard or paper.
(3) Use a standard format for recording the information, as this will provide a memory jog when writing. My current format is fairly simple, and aided by my teacher's organized use of lesson time. As you have seen, I record bullet points of technical and musical things I need to focus on during the coming week, broken out by the musical element (scale, etude, piece) where they were discussed.
(4) Write down everything you remember as soon after the lesson as you can. I usually do this that evening or, at the latest, the following morning.
A fun experiment to try: record your lesson. Over the course of several lessons, do a brain dump at various times from immediately after to just before your next lesson. Compare what you remember with what you hear on the recording. If you are not already convinced that you forget so much so quickly, that will do it!
And the last step to make this a useful exercise is to use your notes at each practice session. A variation on the previous experiment is to do a brain dump after your lesson, but practice all week without looking at your notes. Do a second brain dump just before your next lesson, and compare the two.
I'm in the process of transitioning from one style of practice log to another, yet undefined, style. I'll write more about that later.