I know you said it was wortst practice in your article, but the icy hand of DBA's past gripped my heart when I read about altering system tables.

I am always nervous of changing catalogues, be they system or application catalogues unless I have a guarantee from the vendor that such changes can do no harm.

You would have to have throrough documentation on what you had done and a role back procedure so that all the changes could be dropped prior to the application of a service pack then reinstigated after the service pack.

The problem with altering system tables is that there is no guarantee that the changes will be applicable after an update i.e. MS change their methodology so that XTYPE is no longer used to validate system tables.

When it comes to enforcing best practice I prefer the approach of "Do it right and I'll buy you a pint, do stupid things (more than once) and its the big stick with the nails in it for you my boy"!