I haven't used the specific function that you reference, but it does appear that it is intended to function the way you describe.
FWIW, what I have done when sharing my TCDB lists with potential trade partners on Twitter is copy/paste a specific link to the set-specific list that I want them to see. For example, if they are interested in what '73 Topps baseball cards I have available FS/T, I copy/paste the link to that specific FS/T list to my Twitter message. I do something similar with any specific wantlist that I want to share.
My rationale behind sharing the specific lists rather than the global collection list is that I want my potential trade partners to be able to easily access the specific set list(s) that we are discussing. (They can access additional lists from those links as well, but I like them to have the specific set list right away to minimize the search work they have to do.)
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(As an aside, I think there were some recent issues with non-TCDB members not being able to view the linked lists. I recall seeing something about that in a forum thread, but I wasn't able to find the thread to confirm if there had been any review or resolution of that particular concern.)
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Hope that helps.