preface by saying i am not familiar with the iterations of Byrne's signature.

all I can tell you is, he was trained as an architect, briefly, and archiotects spend so much time drafting early on (as he would have at RISD), that their lettering informs their signature.

if an architect "signs" his name, it will often be the more flourishing script that you see in any signature, like the ones you may be more familiar with of Byrne's.

but this example is less a signature and more a handwritten name. hahaha hard to explain.

but the lettering is entirely consistent with an architect's 'hand'.

which all means, i would not say that it is 'wrong'. it's how we write. he just "wrote" his name more legibly than he did "sign" it.

not an answer. but that's how every architect i know would hurridly write "byrne", including the 'E' with detatched upper horizontal stroke.

i also think the sketch is consistent with his others.

....but you need another example (of that sig) to really feel comfortable i think.