This paper proposes an explanation for the rise and fall of a 1PL imperative ending in the dialect of Mesocco, a Northern Italo-Romance variety from southern Switzerland. This ending cannot be explained with inherited IPL morphology: rather, it is best accounted for by assuming the reanalysis of a 2PL imperative hosting a ISG pronominal object clitic. This reanalysis, it is suggested, must have occurred in the syntactic context provided by the 'ethical' dative construction. It has been prompted by several factors, among which the crucial one is functional in nature, viz. the pragmatic homology between IPL imperative - unmarkedly inclusive in meaning - and the ethical dative construction with a 2PL imperative. Comparative evidence is also adduced from studies in linguistic typology, showing that similar crossovers between 1st and 2nd person plural morphology, although unattested in Romance (or, more precisely, in the better-known standard Romance languages), are not without parallels cross-linguistically. Finally, a functional motivation is provided for the deacquisition of this IPL imperative form in the dialect of the younger generations.