Can I "multi-include" a subtree?

[David Rogers]

Is there a method I can use to include the same subtree in several different 
files, such that editing one instance of that subtree updates the others 
automatically? I'm hoping to be able to view the full version of the subtree in 
each of the files, without having to follow a link; if what I'm describing 
isn't really possible, then I'll just use links in the other files to point to 
the original subtree, which I know how to do. I'm just exploring the 
sometimes-unexpected possibilities. :)

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Thanks
David