Written expression is processed by a different part of the brain than verbal expression. Likely, one of the writers has experience with this with family or friends. Or, found it on something like the TBI Survival Guide or brought in a TBI consultant. TV scripts are not constrained by decades old med school or the limit of the patients of a neuro. But, a speech pathologist would likely know more about this than the doctors.

I find I do much better in written expression than verbal. I attribute part of it to the fact that written expression is slower and allows me to read what I am writing which helps me stay on track and be reminded of what I have already said. Having the ability to edit what I have said also help.

You likely find you are more expressive about old knowledge than new knowledge, especially new knowledge you must analyze.

I find that I also struggle to receive and process spoken words compared to my ability to process written words. I am quick to use the 'skip back' feature on my satellite TV system so I can rewind a few seconds so I can understand what is being said. I wish I had that feature on the car radio.

I find that once I understood these limitations, I was able to develop work-arounds so I could continue to function.