This paper investigates the internal and external syntax of non-restrictive nominal appositives (NAPs), such as John Smith in I met an old friend, John Smith, at the pub. It is shown that the internal constitution of NAPs bears directly on the analysis of the irrelation to the surrounding host sentence, in that a rich internal syntax obviates the need for any direct syntactic connection between host and NAP. It is shown that NAPs are structurally independent sentence fragments that can be freely employed either sequentially (as 'afterthoughts') or as interpolated, supplemental speech acts, autonomous from the host in prosody, interpretation, and syntax. The analysis renders superfluous powerful extensions of core syntax/semantics proposed in previous work to capture the syntactic properties of NAPs and other parentheticals, concluding instead that NAPs warrant no enrichment of UG.