snip
>I don't honestly know how this would affect sourcesafe issues. :-\ But, I didn't like having the situation of wanting one form from a library of forms and getting the baggage of the whole library. Where I saw this was working on existing projects and have several classlibs each with many classes and not knowing which were really used or not.<
endsnip

VSS is a big consideration if you're talking about team development. In a recent project we started out with "buttons in the button class, forms in the form class" but that changed (degenerated?) into task-oriented class libraries as the system got larger - and as more developers were added. That way Joe Blogg could work on the Foo Maintenance section without stepping on anyone else. One person still had to keep an eye on everything - make sure there were no identically-named classes in two different VCX's, that sort of thing - but it was the only way we could keep the pace up.