rodp wrote:Well, that's my little brain frazzled

I have one full name , it's all I've ever needed
can you elaborate or would it not be the done thing on a public forum ?
Foresay, my name is John Rodger Public.
In the US, the very first thing you get is a Birth Certificate, which is issued by the hospital with my full birth name "John Rodger Public", the Certificate is handed over to the State (Local Government) to be stamped and certified.
The second thing you get is your Social Security Card. Social Security is a program that was started during the World Wars that allowed the Federal Gov't (Top gov't in the US) to start a pension act for Vets. It ended up turning mandatory for everyone. You are issued a number and a Federal Bank Account. This is really the first and only form of Fed ID in the US "provided you live as a recluse as an adult". That card is printed with my full birth name "John Rodger Public".
As a child (if you're old like me, I don't know how they do it now) You get an inoculation card. I don't remember who it was issued through, it's a defunct program. But essentially you have to have this card to register for any form of school. Card said you had mandated vaccination for Polio, SmallPox, Measils, Mumps, Rubella, etc. That card has the name "John Public"
Here's where the fun starts...
In you're late teens, you get your drivers license. It is issued by the State. You can put what ever the heck you want on it. It could be "John Rodger Public", "Johnny Public", "John R. Public", whatever. I took "John R. Public" because that was the way I was used to signing documents. And, at the time, it wasn't a big deal to abbreviate a middle name, or leave it out altogether. In the US, the "Driver's License" is the "Ace Card", it is taken as Interstate and Federal ID. If I get stopped by the police in a different State in the US,...I can had the police my Passport, my Certificate, etc...they are unacceptable forms of ID...if I don't hand him a Driver's license, I'm going to Jail.
At 18 you are allowed to register for Voting Rights. For all males that wish to register to Vote, they must also register for what is called (Selective Service)...essentially a military draft. So, here goes two forms of legal registrations, that now have "John R. Public" signed and printed on them. Now I'm in a mix of numerous ID's with numerous names.
When you graduate from college,
the important ones with real degrees, it's customary to pick a legal name. I went with "John R. Public MBA, PhD, etc". This can be considered as a legal, professional name. I work in health care. I have to sign legal documents with the "John R. Public MBA, PhD, etc" in order for stuff to get done around the hospital.
Now let me digress back to OP...
I'm old. My name has changed around in life. I get my Passport,
through the US gov't, I have two very different
and used names. The passport says "John Rodger Public", my legally recognized signature is "John R. Public". Now what do I do?
It could be worse. Plenty of married women choose to hold onto a Maiden Name, change to the husband's name, or "hypohenize" the two names. The two or more names they end up with aren't even close.

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