I am helping a group of statistical and genetic analysts maintain an R environment for their work. One key capability that is required is the ability to reproduce previous computations. The R packages that were used for an analysis are typically recorded.
For CRAN, it's easy to find the tar-ball for any published version of any package, but that is not the case of Bioconductor. The directories that contain tar-balls for versions between releases are not indexed, so the only way to find a specific version is to try the URL, which is really inefficient and not practical.
Would the Bioconductor developers please consider making all published tar-balls available in some easy to find way? I understand the need for having a consistent set of packages so incompatibilities are avoided, but the current situation makes it very difficult for those of us facing an auditor who wants us to reproduce a five year old computation.
One suggestion that I could offer would be to put the tarballs archive behind a user account system (as is used by this forum for posting messages) and have the user see a clear statement that the tarballs outside of releases are not supported or recommended in any way.