I've been writing commit messages this way for a little under a year (I think this is the same guide I used when I was looking for a more consistent form to write them and to avoid the dreaded -m "Fixed some things").
One thing I noticed is that it's increased my confidence in my commits; at the moment that I go to write the commit message because I'm describing why I made the decisions I did it breaks logical inconsistencies between what I've actually done and what I think I've done. If I'm able to explain all the change I'm much more confident that it's correct.
Another is that bad commit messages have trained people not to read them. Often people will ask why I've made a change and then discover that the commit message contains the answer to their question!
One thing I noticed is that it's increased my confidence in my commits; at the moment that I go to write the commit message because I'm describing why I made the decisions I did it breaks logical inconsistencies between what I've actually done and what I think I've done. If I'm able to explain all the change I'm much more confident that it's correct.
Another is that bad commit messages have trained people not to read them. Often people will ask why I've made a change and then discover that the commit message contains the answer to their question!