Re: How do I put a global effect on 2 composited clips?

Neither way would work totally in a transfer via EDL.

The nesting won't work at all. You could export an EDL for the nested sequence separately, but that's not really practical.

The export/import method (essentially the same effect as a Video Mixdown in Avid) is another option. However I would put it on a video layer above your underlying layers, that way you'll still have the stuff on V1 and V2 that builds the shot, and you can work on the comped effect on V3 as a standalone clip.

The thing that I really miss about the Avid effects paradigm in FCP is the clarity. Using either of these methods in FCP results in sequences that are somewhat unclear - with a 'baked' shot you have no reference back to the original at all. With a nested sequence you have some reference back to the edit, but it's not clear without going into it what is happening there. I can always see exactly what's going on in a single timeline in Avid, that isn't really the same in FCP at all.

Personally I'd really like to see FCP offer some way of doing something like the effect-on-filler thing in Avid, which would more aptly be viewed as an adjustment layer I suppose.