Make a duplicate of primary storyline (as a secondary storyline ... without losing transitions)?

So this will seem like an odd request so I'll explain the need.

I'm editing a film to be projected onto a sphere using a rather complex 4 projector system. Basically the system takes my traditional format, cuts it, handles all the overlap and brightness fall off. It's quite slick.

But, this means I need to take my primary story, mask and translate it to be one side of the sphere, make a copy and do the same to be on the other side of the sphere.

I have done this where I used a still image as the primary story and had two different connected clips of the actual film edit as secondaries.

The problem is I really want to refine the edit, complete with effects and transitions, as the primary story and then just make a copy and apply a simple translation to be sure all the transitions, etc. are identical.

I have not found a way to do this (but I am not a massively experienced FCPXer)

My finished result should look like a static image (but actually with some animated effects in Motion) and what looks like two, in sync, PIP copies of the actual film edit (see attached file)

Any thoughts or do I just have to resign myself to a painful process due to the bizarre projection system?

I am not sure I entirely understand your post, and there is no image attached. From what I can infer, you could make a compound clip of the entire primary storyline by selecting all the clips in it and pressing Option and G. Then you can simply duplicate that compound clip by holding the Option key and stacking it above the main storyline (or anywhere else). You can do this multiple times if you want more than one occurrence of your main storyline. If you are not familiar with compound clips, you should check in the user manual to see the various options for creating them. By default, once you create the compound clip, any changes you make within it will trickle through to all instances of it. To edit clips and transitions inside the compound clip, simply double click it to open it up. Close it back up by using the back arrow that will be located just beneath the timecode window (where the project name typically resides). You can, however, reference a new parent clip when you make it so that changes in the parent clip will be unique and not affect the newly created one. In your case, from what I understand, the standard compound clip would do what you are asking.