I wonder what makes the memories? There are certain events that have left me with the most vivid unforgettable memories (some of these events are my dreams). Yet, writing my master's dissertation, has left practically no memories, though it has profoundly changed me. I can easily say that I became my master's thesis, however, I most completely do not remember writing it.
Now, that I have written it, I have a hypothesis. I think it is a sudden change that is to blame. Gradual achievements accumulate step by step almost unnoticed for the brain. I also never remember running Comrades - another significant life-changing experience. Step-by-step - it is the same, and just suddenly you are 90 km away from the start. That was the same with my master's - step by step, starting from Peter Drucker's works - and suddenly, I am a different person, criticizing relentless and thoughtless money-making. "There is nothing so useless as doing efficiently that which should not be done at all."
On the contrary, I vividly remember a bright green grass dream in some gray cold winter in my childhood. It was so different and happy. Change..difference...A brain is a funny tool. And change is good - at the very least - for the memories!