To put a stake in the ground, I'd suggest that any query only deal with one of the N date fields, ordering of that field, limiting to start/end range of dates, and applying a maximum count limit.
http://bobwyman.pubsub.com/main/2004/09/using_rfc3229_w.html http://msdn.microsoft.com/library/en-us/e2k3/e2k3/_exch2k_sql_range_header.asp