Force a pruned checkout by default

[Christopher Sean Morrison]

Is there any means to force pruned checkouts or make them the default 
server-side?  I know that users can add -P to their config or to the 
checkout line itself, but alas too many users are not aware of this 
fact.  Likewise, we end up spending/wasting too much time telling 
people they need to prune because of that default behavior.

The package in question is several decades old and has undergone 
several reorganizations, refactoring, and renaming while mostly 
maintaining all history.  Removing the directories themselves from the 
root, of course, is not an acceptable solution for the sake of 
maintaining that history.  The size of the package is on the order of 
several hundred directories give or take a hundred that have mostly all 
moved over time in some way or another.

My hope is something I can put into one of the CVSROOT administrative 
files?  Thanks in advance for any advice.

Cheers!
Sean