you could lasso all the video and make a new compound clip out of it and then just highlight it and drag it to the primary. Some editors like to work the way you did this, connecting everything to an empty primary. as you seem to have discovered the problem with this approach is that the primary has some abilities that the other story lines do not such as the ability to connect another clip to it. I really don't get why they don't allow you to have a secondary story line with its own connected clips. If this were unlimited then X would pretty much have the equivalent of tracks only with visual connections.
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