How do #(break-thread) and &(link-threads) work

[Olivier <olivier@xxxxxxxx>]

Hello List,

I have a question regarding the way #(break-thread) and
&(link-threads) work.

When I discovered those two features yesterday, I thought that:

  # deleted In-Reply-To and References headers
  & added In-Reply-To or References header

When trying those two features, I think I could verify the first
asumption, but not the second. I can't see any new In-Reply-To or
References header in a just-linked message.

So my question is:

I am right (and then how does mutt recognize that the newly linked
message in indeed part of the thread it was just added to) or am I
wrong (and then how can I be, are my glasses (or brain) broken ? ;-)

Best Regards,

-- 
Olivier