I'm not really familior with them, AVID jut treats any empty section of video track as a clip and I can apply filters and effects to them as I can with a normal clip.
I find this usefull when applying filters as transition effects, for example I can use a plugin (lets say Glow) and apply it to 8 frames on the layer above an edit and then alter the keyframes and parameters to create an interesting flash transition. I can do the same with Lens Flare and Paint and all the other effects in the pallete
I find this easier than having to apply the same effect to the last 4 and first four frames of the in-coming and out-going clips.
So I tried to do the same in FCP and it didn't let me.
Then I discovered slugs and I thought I had cracked it, but no.
I tried adjusting the opacity of the slug but that didn't work.
So what am I doing wrong? Can I apply effects in the same way as I am used to on AVID? Am I making sense?