Why does "Reveal in Event Browser" only add the event to the browser?

iMovie 9.0.4, OS X 10.6.8

OK, I select a clip and execute the Reveal in Event Browser function. IMovie then finds the event that the clip was taken from, adds it to the event browser, and outlines the appropriate portion of the event in yellow. That's fine, but why does it only add the event to the browser? Why are the events that were previously there not removed from the browser?

IOW, say I have several events, but only event 1 in the browser. Then I select a clip in the Project Browser and run the Reveal in Event Browser function, and it brings up event 2 with the selected project clip's portion of the event outlined in yellow. That's fine, but why is event 1 still in the browser? You can repeat the process and if the event isn't already there, it just adds it without removing the previous events. Is this by design? Or is it a case of, "It's not a bug, it's a feature!"?

Wow! I just tried it again and it added all the events from my "external camera"! I would think one would want only the one event the selected footage is taken from.

--AEF