I earned a BA in psychology. I did so in a unique college that was based on independent study and essay writting. More so than most students we were required to do research and give presentations on our subjects. 2 credits of every 8 credit course were based on this area. Almost all exams were essays. Our classes were usally a circle of chairs or desks and discussion based.

In terms of knowledge, it made, in my opinion, a huge difference. We had to process the information more deeply. There is a big difference between recalling a term and circleing "c" on an exam sheet and having to either orally or verbally in scribed words explain the concepts.

The more you think about something, the better the associations become in your cognitive schema. You build stronger "links" to the material. The more different methods you use to process this knowledge, ie. writting, talking and discussion, the more "links" you build. (The psychological term is usually tag or hook but I am just being web 2.0ish as a pun. Puns btw are also mnemonics.)

The processes of discussion, writting and feedback are more than just reflection. They are all vital to comprehension, retention and, especially for writters, expresion. Trying to establish linearity or any other pattern to something that is as complex as the human brain is going to be a grey matter for sure. ;)... I'll stop now.