For still GFX needing transparencies that I will eventually use in FCP and Avid systems, I always use TIFF files that I have checked "use transparency" when saving them out. They always work fine.
I was wondering why then it is necessary, as is done in many of Richard Harrington's great tutorials, to bother creating an embedded alpha channel. Is there some difference in the way the transparency is interpreted by the NLE/compositing app? Just wondering. Both methods seem to yield similar results. Any insight would be greatly appreciated -- much thanks.