Ignoring additional records works pretty well for me.
This is harder than it looks. Sometimes the glue A RRs are the only ones
you can get -- you need them in order to ask questions in the domain they
are in, so without them you have infinite regress.
We are planning to store these glue A RRs as query-temporary data shortly,
such that they can be used to try to refetch themselves but will never be
returned as answers to any other query.
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