The poster is doing this in addition to actually writing the notes - I've done something similar. Sometimes I take the initial notes on a computer. Later I hand-write them once or twice. Once immediately and once later on to narrow focus down on things I was having more trouble remembering.
The biggest benefit is that such a system gives some repetition. For me, this repetition is superior to only reading notes because I wind up working with the information physically as it changes form. I do get better results in some subjects if I work plenty of problems in addition to this - for example, foreign/second language and maths.
The only times I've found this sort of thing generally unhelpful is with things like music, art, and physical education/sports. These rely on a lot of muscle memory, and it is hard to get by writing.
The common thread in all of these is practice and review. The main difference is in the way they are carried out.
Typesetting gave me a set of digital, neat lectures notes (goodbye folders of paper). I also understood everything better because I'd read through it twice. Most importantly it was good bargaining material for skipping lectures and getting notes from other people.
I also flash-carded all my lectures in 3rd/4th year which undoubtedly bumped my grade up. The key was timing it so your peak recall was at the exam, given the volume of information. It was useless for long term memory though.