I find --help usefull as it lets me call help up while im modding a command
For example
rsync -vPn ./* ./newfolder/.
Oh What is the dam flag for compress?
rsync -vPn --help ./* ./newfolder/. | less
I find the help command on flags sometimes very very usefull and less time consuming. With man ive gota type it in and the go back through my history to get back to the command I was in.