Thread:Project:Support desk/Shared user table, shared user pages?/reply (2)

The page's cannot be shared in the same way that the user table can be.

This sounds like something that would make a good extension (even if only for crappy inclusion of user pages, akin to image description page transclusion from foreign repos).

Not really solving your problem, but you may be interested in Manual:$wgEnableScaryTranscluding