Updating Drupal modules through SVN without leaving old files in place

The title of this document may sound contradictory and unclear, but the detailed statement is: Looking for a way to maintain versions of Drupal core and modules in SVN-Subversion over time, and still be able to have clean files on the development and production server without risking old files that may prevent the application from functioning properly.

I have realised that as long as the new module-files of any given modules are equal in number and file-name to the older version, then there is no problem with simply loading the new files into SVN, creating a tag or -r revision number, and then doing an svn update -r 1234 to pull down the updates to the live server. The problem arises when a newer version of a module doe snto have a file that was there in a previous version of the module. In such a situation, the safe answer is to actually delete all the files for that module from SVN or create a new branch and load the fresh new files. This approach will ensure that old files do not continue being called by Drupal and potentially causing problems (especially if these files are *.module files).

I expereicned this problem with the filefield module a few days ago when I updated it by simply addign the new files to SVN and then doing a checkout from the application server. Drupal started listing two version sof the same module and there was an application failure. My objective henceforth is to find a way that I can keep old milestones of a module and still be able to checkout new updates of a complete application and modules from SVN without worrying about carrying along a file that should not be part of the application that can potentially cause errors - maybe my question should be whether I really need to keep old versions of a given module or core release since that is always available from drupal.org... But my OCD makes me want to keep every complete milestone of my deployments over time (that is why I love SVN so much) and I need some middleground.