Well for one that's totally useless with regard to user behavior because people aren't signing in and out constantly. The typical user journey (and this applies to 99% of users) consists of connecting, authenticating, playing for a while then quitting. The cache hit ratio would be like 1%. This isn't an issue stemming from a handful of users disconnecting and reconnecting repeatedly.
Secondly, authentication is one of those things you shouldn't cache, and certainly not for an hour. I'd rather the service wasn't running than have it using stale authentication results which could be used in a variety of ways to cause trouble.