Re: Apple article on Optimizing Media

But that's my point. Besides using a different framework which has better realtime playback performance, as far as rendering is concerned there is no difference between FCP7 and FCPX.

In FCP7 you choose a sequence preset with a certain codec, which you can alter to some extent while already working in the sequence. If your sequence is in ProResHQ and you drop this type of content in the timeline and make only cuts it will just copy over these segments to the QuickTime file on export, however any adjustments or filters will be rendered.

In FCPX you don't have to specify a codec for your sequence. But if you make cuts only and use export media from the share menu with 'the codec that you have used the most within the project' (actually it is not current settings, this will create a ProRes file)  it will also just copy over the editted segments to the QuickTime file if your media has the same codec as the chosen codec. When filters are used it has to render but FCP 7 had to do that as well, then it's not 1:1 anymore and then smart rendering doesn't apply.

What's the difference? IMHO there is none. Try it, test it and report back.