I'm sorry, but was this intended to be a replay to my node? I made four very specific points, none of which you specifically addressed.

Having a separate installation that is installed by the user for his own use is a good idea (and a best practice, really), but it is not strictly necessary if perl is installed and configured completely correctly.

It's a quite bad idea, IMO, to provide two separate installations out of the box as merlyn points out so humorously. A savvy user should install one's own. A less savvy user either won't mess with the system perl or shouldn't.