I apologize, but you are indeed right. If you are a superadmin you can't edit your name. No reason for that, but that is the way it is now. I am never logged in as superadmin, so I hadn't noticed it. AnonJr's suggestion is the easiest way to achieve that. Try it.
Ruirib, thanks for checking it out further for me. I'm too new at this programmingt stuff to feel safe trying what AnonJr suggests. My site is getting some decent exposure, and participastion on the forum -- I don't want to put things at risk. My web designer had entered my name, without thinking about what my preference might be; perhaps it will be mistaken for extra humility.