The i/upsilon cluster theory of vapor phase nucleation has been presented in a series of papers of which the present paper is No. V., The theory has experienced some evolution throughout this series. In the first paper an attempt was made to use the classical cluster of Lee, Barker, and Abraham (LBA cluster) that is so attractive for computer simulation. Among other things, that theory uses a so-called "shell molecule" that does not interact with the remaining molecules of the cluster. We show that this "decoupling" of the shell molecule leads to a result that is not internally consistent in the sense that dimers (which are really single vapor molecules) do not have the right concentration. We show how to repair this inconsistency so that the decoupling approximation can be used and, with it, the useful LBA cluster.