After trying many different ways to get Google Spreadsheet to allow IFs, MAXs, MINs, SUMs, FILTERs, SUMIFs, ARRAYFORUMLAs, etc. to be evaluated per row across the columnar range (multiple single-column ranges were involved in the calc, but they were all the same size and everything should work if I could get Google to treat each row as a DB-entry type thing,) I gave up and refactored my table of events so that a single event spanned multiple rows and each row represented a single calendar day. That is, the above Sheet A now looks like:
Sheet A
| | A | B |
|1 | Event1 | 1/15/2013 |
...
|17| | 1/31/2013 |
[18| | 2/1/2013 |
...
|38| | 2/20/2013 |
|39| Event2 | 3/1/2013 |
...
|49| | 3/10/2013 |
|50| Event3 | 5/7/2013 |
|51| | 5/8/2013 |
|52| | 5/9/2013 |
This way there were no complex range vs range intersection calculations so a simple FILTER() based on whether the event day was within the querying range period worked.