-library. It may be necessary for you to add some version dependancy
-information to the shlibs file. If -V is specified with no dependancy
-information, the current version of the package is plugged into a
-dependancy that looks like "packagename (>= packageversion)". If -V is
-specified with parameters, the parameters can be used to specify the exact
-dependancy information needed (be sure to include the package name).
+library. It may be necessary for you to add some version dependency
+information to the shlibs file. If B<-V> is specified with no dependency
+information, the current upstream version of the package is plugged into a
+dependency that looks like "I<packagename> B<(E<gt>>= I<packageversion>B<)>". Note that in
+debhelper compatibility levels before v4, the Debian part of the package
+version number is also included. If B<-V> is specified with parameters, the
+parameters can be used to specify the exact dependency information needed
+(be sure to include the package name).
+
+Beware of using B<-V> without any parameters; this is a conservative setting
+that always ensures that other packages' shared library dependencies are at
+least as tight as they need to be (unless your library is prone to changing
+ABI without updating the upstream version number), so that if the
+maintainer screws up then they won't break. The flip side is that packages
+might end up with dependencies that are too tight and so find it harder to
+be upgraded.