I take notes about company IP in a notebook _all the time_. Part of my job is to document the things I learn about or create in my notebook, precisely so that we can establish a work timeline on a piece of technology if necessary.
I keep dedicated work notebooks, and while most of the time it's a way for me to Write Things during meetings to make sure I prioritize tasks and whatnot, I have quite frequently used them to document new things I'm learning about. Almost anything non-trivial is worth writing about, sketching about, and diagramming the major pieces and relationships. Whether it's a piece of infrastructure that our team might use for packaging and deployment, a workflow for a tool we are building (or needing to cooperate), or even just something cool that a co-worker is presenting about, it ends up in my notebook.
I keep dedicated work notebooks, and while most of the time it's a way for me to Write Things during meetings to make sure I prioritize tasks and whatnot, I have quite frequently used them to document new things I'm learning about. Almost anything non-trivial is worth writing about, sketching about, and diagramming the major pieces and relationships. Whether it's a piece of infrastructure that our team might use for packaging and deployment, a workflow for a tool we are building (or needing to cooperate), or even just something cool that a co-worker is presenting about, it ends up in my notebook.