I know that but what if the person do not realize there is such action to begin with, he would not what to type in first and have to fish it.
I think it matters whether the person is familiar enough with the system. I think you remember most, if not all, of them but for many beginners like me, it will take some time to remember what is available. A quick look at the list may be faster. I personally find it useful as I just use it to do programming which I find the reference a help. Maybe, there are other members like me.