I haven't read any comics in about 15 years and I don't think this was ever explored back then. In the comics, Wolverine's healing ability has been so powerful at some points that he has regenerated back from pretty near nothing. Have they ever done a story line where parts of his body separated from him basically grow back as a complete clone? Say, he loses his hand, has that hand ever grown back an entire copy of him? Has there ever been an explanation as to why something like this hasn't happened?
I don't recall anything like that happening, nothing like the Meta-Crisis Doctor. Currently: As of Spoiler: Paul Cornell's Wolveirne Logan has lost his healing factor
Most likely, the body parts still have to be connected to Logan's brain to regenerate otherwise it's just flesh and if it regenerate it would just be some blob monster. Logan did regenerate from a drop of blood once, but that was due to magic and not his powers.
I would so enjoy the real Wolverine returning and the current one turning out to be something that regenerated from leftover parts some time in the past. Way in the past.