+ - document optional use of Class::XSAccessor with caveats
- fix constructor generated when creating a class with
create_class_with_roles when the superclass constructor hasn't been
generated yet
currently global and turns the mechanism off entirely so don't put this
in library code.
+=head1 MOO AND CLASS::XSACCESSOR
+
+If a new enough version of L<Class::XSAccessor> is available, it
+will be used to generate simple accessors, readers, and writers for
+a speed boost. Simple accessors are those without lazy defaults,
+type checks/coercions, or triggers. Readers and writers generated
+by L<Class::XSAccessor> will behave slightly differently: they will
+reject attempts to call them with the incorrect number of parameters.
+
=head1 MOO VERSUS ANY::MOOSE
L<Any::Moose> will load L<Mouse> normally, and L<Moose> in a program using