[spazmatastic]

Jimmie doesn't link the J's and this definitely is 2 letters linked together. I think you are right that it is upside down in the pics though, Tom. It does start from the right side and move left in the pics above.
I'm wondering if it might be a crew chief's signature. Maybe he signed the tire before a Goodyear check so he knew it was their tire.

[dunnere]

It's not a logano. Got one signed at the Kansas race last year and it's all spelled out like on the cards. Got 2 jimmie at track autos and he dots over the J with them too.

That's the glaring omission on this that I immediately noticed when re-looking at it...without the two dots over the first J, I'm skeptical. And Adam makes anothe rgood point about linking the two Js.