Hi, I can see what you are referring to. I have 2 examples of Clarences`s signings here, probably from the same signing on the Bruce Springsteen the E Street Band "Reunion tour" 1999-2000. They are quite similar, but with a slightly different "C" and space between "C" and the rest of the name. They are both real and from reliable sources.
Hope this can help, and a discussion around this is very welcome and fruitful in my opinion.
You thinking about the L and S on your first picture?
More generally I will say that I think all 4 shown here are legit, but from different time periods. The ones I shown from around 2000, the one from A.B. probably earlier (80`s?) and yours is probably around 2005, closer to his death.
Some difference, but certainly more consistent signatures than his Boss, Bruce..