I think "pointless" is going a bit overboard, it's up to the client to decide how long to cache a feed, and the cache policy for the feed should use normal HTTP

I think "pointless" is going a bit overboard, it's up to the client to decide how long to cache a feed, and the cache policy for the feed should use normal HTTP conventions - the Last-modified, If-modified-since and Expires headers. If the feed expired in 60 minutes that would be enough to update for changing locations.