I should explain, we are a mega church - we put all attendance to all our services on the event tab. If we wanted to send emails to people that had attended 6 times in the last 4 months, I'd have to export all the records, use a pivot table in excel, then import back to BBRE adding an attribute with the number of times a constituent had attended in 4 months. As this information is a photograph in time, I must do this process every time we want to send communication only to people that attend regularly. There should be a better way.

Yes, I'd also like to be able to query and export on the number of events someone has registered for or attended (with the ability to apply other criteria similar to gift summary) so that this can be used in combination with other constituent and donation information. The number of events can be a good indicator for someone's engagement with the organisation and thus a great thing to be able to query on and export.