That's the third hump of the "M", IMO.
disagree. when have you ever seen a Macca signature without a fully formed M? that is the third hump of the M.
I agree that in most autographs of Paul the letter M has a tail - an extra first line that doesn't belong to the M or to the L - it only connects the L with the M. It's not the case in my autograph. In my autograph the M doesn't have a tail and that's why it has two humps and not three! In my autograph the L and the M are sharing the same line! The end of the L is the beginning of the M - exactly like I showed in my sketching
The letter M begins where the the letter L ends. The letter M is in the red circle and it has only two humps. The first C is in the blue circle and the second C is in the brown circle. In rushed autographs of Paul the beginning of the M is sharing the same line with the end of the L. The M doesn't have a tail here and this is why it has only two humps in this autograph and not three. In rushed autographs Paul signs "Paul McC" (M has two humps) and not "Paul Mc" (M has three humps). You can always say that the M has three humps and by doing so cancel the second C and make it the first and the only C in the autograph. Both versions are right because this is connected English writing. It all depends if in your opinion the M has a tail in the beginning or not.
I would rather have an authenticator err on the side of caution, than pass something that is fake. There are a lot of Macca forgeries out there and if something looks atypical, it should be questioned.
the point is that the third hump is atyically higher than the second one, and that is why it was questioned. While there may be others like this, the vast majority of authentic Macca signatures, if you check them out, do not exhibit this characterisitic, in fact, in many cases the humps are equal.