Why couldn't UserLand just put...

#metaMSSmartTagsPreventParsing "TRUE"

...in the root table of each of their websites? The ability to add random meta tags using that pattern of directive was added to Frontier the website framework in Frontier in version 5 or 5.1 IIRC.

Update: Turns out they wanted to do this for sites that weren't served with the website framework and even ones where meta tags had been disabled.

That would break pages that weren't intended to be HTML, mind you, but if you really want to turn off Smart Tags I guess that's the way to do it.