Alastair,

You can already do this.  Just use this option.  You can also do this from the Member Report.

Love this idea!

Hey Rob, Let me jump in. It's currently designed this way for performance. Can you imagine the complexity to look up all the events "on the fly" for each event and check all the restrictions for each logged-in member? This system would be under a very heavy load to do that. We do have a feature coming in our next release to allow you to convert a dynamic group into a static group to make this easier. We may look at this in the future, but right now, we plan on leaving this at the static groups for now.

Thanks!