I guess a 1 minute time out for the data reload wouldn't be too harsh, aslong as the page requested minimal queries, like the session, other requirements and then the data itself.
Depends really how active your site is, a site with 100+ users on most of the time would really need to put the time out higher, say 3/4 minutes, but the content would still remain intact.
But things like getting last x posts would only take 1 query, you could even use the XML output as a feed for your main site
- Zero Tolerance