Unstressed bin is the African American English (AAE) verbal form occurring in sentences such as I bin paid that bill last week ‘I paid that bill last week’. Contrary to what has been claimed in much of the literature, unstressed bin does exist in the grammars of some contemporary AAE varieties. Unstressed bin occurs in many clausal environments where it can be mistaken for stressed bin, which is not always stressed, and the past participle been, which in many English varieties, AAE and other, may occur with the preceding form of the auxiliary have deleted, as in I Ø been at their house many times ‘I've been at their house many times’. Complicating matters is unstressed bin's occurrence in the homophonous I bin at their house many times ‘I was at their house many times’ and ‘I've been at their house many times’. The concept merging labels this process, whereby AAE forms such as bin occur in identical syntactic environments with homophonous but grammatically distinct forms, creating a type of grammatical camouflage. More important, merging is part of a larger process of mainstreaming, whereby one language variety, AAE in this case, converges qualitatively and quantitatively over time toward a sociopolitically dominant language variety or cluster thereof. The notion of mainstreaming avoids problems with the notion often used in creole studies, decreolization, which can obscure fundamental events in the genesis and evolution of AAE. Recognition of the grammatical status of unstressed bin, along with the consideration of other heretofore undiscussed or little discussed AAE forms with creole language counterparts, prompts a call for revisiting the question of whether AAE may have U.S. mainland creole origins.