I got the impression romulus actually restored him to a previous natural state that had been compromised by all the programs he was subjected to. There was a story in which logan remembers having fought wildchild in WWII and he looked and fought exactly like the romulus version.
No, as he became faster (even noted to be faster then Wolverine), had posionous claws that put Wolverine to sleep for 2 days (not sure if that's standard) and rumor is he was bonded with adamantium too.
I think his speed was a restoration of his original form, along with his wildheart appearance and persona. The claws were dipped in poison, he doesn't secret the toxin. Unaware of the adamantium, but it sure is possible.