RE: frameset-to-register

[Drew Adams]

> This code adds a new frameset-to-register command.
> 
> Assuming that it is OK to install it, keybindings in the C-x r space
> are scarce. I propose to bind it to C-x r F, which is already co-opted
> by frame-configuration-to-register (via C-x r f) and seems mnemonic
> enough.

Why does this not just replace `frame-configuration-to-register', i.e.,
C-x r f?  What are the differences?  In particular, what, if anything,
does `frame-configuration-to-register' let you do that
`frameset-to-register' does not let you do?

I understand that a frameset is Lisp-readable, so it can be persisted.
But it's not clear why one would use `frame-configuration-to-register'
if `frameset-to-register' is now available. 

I can guess that `frame-configuration-to-register' might be quicker,
but what are the real, user-level differences that would mean that a
user might want both to be available (and bound to keys)?