Remove: Object running along a background. Which way?

Mocha Pro: Tips for Faster, Better Object Removals - YouTube - Background layers corrected with keys

mocha Pro 5 Plug-In: Remove Module Quick Tutorial - YouTube Background layer unlink.

Do those 2 methods bring about similar results? It seems to be the first method is the common sense and the second is kinda a meddling and tacky. Or am I missing something?

It really depends on the shot.

If there’s parallax between FG and BG you’re going to have to approach the shot differently than if they camera is basically showing a single planar movement behind the object.

How does it even matter? It’s just about unlinking vs spline correction. If you unlink if works as a scanner you youself say it in the video. Tracker still does the same job doesn’t it? If you correct the spline with keys over time cos it’s linked and get wacky cos of the background how is it going to help the shot better?
Mind you I’m not talking about tracking one BG VS 2 due parallax. I’m talking about unlinking vs manually keying flying away all around a place linked spline

It matters because if there’s any drift in the BG track because you’re tracking multiplanar objects, you will get a predator effect in your remove, where it looks like something is rippling almost invisibly from the shot.

I understand what you are asking and I am saying your results for the FG shape will vary based on what kind of track and motion is happening in your BG shapes. Removes use the FG shape to say where to remove and the BG shapes are used to tell it “how” to remove those objects. If they’re not perfect tracks, a shape that moves might give you poor results.

Ok where can I get that running dog footage to try the scanner method to compare?

It’s been a while, so I am not sure, but I think I got it from Pond 5 and paid for it. So I can’t share the footage file. But you might be able to find it on Pond 5.