It is true that the Disciples section could become quite large!  Our criterion for the initial selection of disciples was that all of the first four arguably co-authored with Whitman in one way or another.  So in that way, at least in our initial conception, the Disciples section keeps a link to the author-centered way of conceiving of how to organize information. However, the <em>Whitman Archive</em> explicitly tries NOT to be unduly limited by author-based conceptions of what is relevant, so we include reviews and criticism that no one would claim should go in a traditional "collected works of [name your favorite author]."
 
You ask a really interesting question about the boundaries of the <em>Archive</em>.  In a sense: are there any? and if so how do you establish them?  The question reminds me of a great remark Henry James made in <em>Roderick Hudson</em>: "Really, universally, relations stop nowhere, and the exquisite problem of the artist is eternally but to draw, by a geometry of his own, the circle within which thy shall happily <em>appear</em> to do so."  Ultimately, no doubt, everything in the world is related to everything else, if we had only the wit or knowledge to understand all the connections.  Weather patterns in Patagonia probably were somehow connected to how Whitman wrote his poetry.  But some things are more clearly and closely connected than others.  So in constructing something like the <em>Whitman Archive</em>, with limited time, money, and staff, it makes sense to work on the most important things first, to establish the most important connections, to fill the known scholarly gaps, and to respond to what we know (not enough) about the interests of our various audiences.