Certainly, it's good for spiders to hit 'Recent Changes', and often.

Why? The spider doesn't know that the pages on RecentChanges have had recent changes. It's just a list of links, like special:allpages or special:ShortPages.

Maybe one could add /wiki/special:RecentChanges& to the robots.txt file; that way, the spider would fetch only one copy of RecentChanges, not 14.

Axel