Hold on!
Did you actually, originally, get 3 SEPARATE clips or not? When you captured your footage to your hard disc, did you capture as just one BIG clip OR did you capture using the "Enable DV scene detect" option? Sounds like you could have made use of that?
Anyways, when I want to PASTE an Fx to multiple EVENTS I click on the Event that has the Fx applied and go:
#1 - Copy
#2 - Select the "other" events by use Ctrl+LeftClick - the selected events remain selected
#3 - Right Click and choose "Paste Event Attributes"
Done!
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