EWM Work Item in GitHub Pull Request

I have a hard time understanding the last sentence and the use case. I am also not really fluent in Git and am unsure in which UI, if any, this use case happens. You might want to expand on the question and its background.

Note, that few people can comment on design decisions on this forum.

Pleas also be aware that the Jazz Community has provided some custom enhancements for the GIT integration: https://github.com/jazz-community

The crux of the question is:

As for the last sentence, git commit messages (by convention?) have a summary and a body. The reason I say "by convention?" is the help for the git commit "-m" option states that specifying muliple "-m"'s creates a new paragraph for each "-m". The first line (paragraph) is the summary (I have worked on some projects where they have a hook to limit the summary to 80 characters). Specifying a work item pattern in the summary or in a later paragraph of a commit message triggers linking.

Garret, no, I think this forum is the right place to ask, I just do not have the knowledge to understand and answer it.