Template:Event

This template provides a standard format for event pages. It takes the following arguments:

{{Event
|description = a short summary description of the event (Property:Description)
|occurred = when an event occurred (for instantaneous events) (Property:Occurred on)
|start = when the event began, or when it is scheduled to begin (Property:Start)
|end = when the event ended, or when it is scheduled to (if at all) (Property:End)
|location = where the event happened (Property:Has location)
|a = agent/cause/creator/instigator of the event (Property:???)
|b = person affected by or otherwise relevant to the event (Property:???)
|c = events directly caused by this event (Property:???)
...
}}
How useful is it to have separate properties for separate namespaces? The idea of a,b,c is to allow chains of cause and effect to be worked out.
A is_immediate_cause_of B, B consitutes War, => A constitutes Casus_Belli and the like...