Linking a user profile in JR site to the user's profile in another social network...how exactly?

In a profile settings dashboard, a JR network member will see this help message when trying to link their JR site profile to another social network. What does the instruction really mean? It looks like a loop. To link this profile to another profile from inside JR, the other profile in the other network must already be linked to the JR profile? Does this mean other networks don't require the JR profile to be already linked to them? Why does JR have this requirement? Since I don't already understand the process, I don't understand the message (sorry).

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Quoted JR help message:
Select the external social networks you would like to link to your account - note that you must already have an account on the linked social network, and have linked it to your account in order to link your activity stream.


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PJ Matthews, Kyoto
Migrated from Ning 2.0. Now at Jamroom 6 beta and using Jamroom Hosting for The Research Cooperative (researchcooperative.org)

question is not clear. It sounds like you're looking for a way to allow your current users to let other users know of their presence on other social networks.

If that's correct then one way to do it would be to add some custom fields to their ACCOUNT SETTINGS -> PROFILE form to allow them to input what their other locations are then display those on their profile so the other users can click on it to reach them in the other locations.