Either a shift of info or a merge of the pages.
My case:
Mr. Gold (the persona) was only truely seen in Welcome to Storybrooke, Saving Henry, and a little in the Pilot.
It has been confirmed by the writers/ showrunners, that Rumple regained his memories since he met Emma in the Pilot. Spoilers!
In that case he has been Rumple since the Pilot and Mr. Gold has barely been seen since. (I know they call him Mr. Gold, but David calls Snow MM and Snow, so what the characters call each other makes no difference.)