I'm willing to be corrected: does anyone want to document a single
case where this was required _by_the_IESG_ in the last two years?
I only know of one case where it was even discussed. The IESG felt that
it was necessary to tell the WG that such a requirement was needed in
their charter. Since that was not the case, the discussion was abandoned.
The IESG concluded that it could require interoperability testing in the
future only if the WG was warned ahead of time by including the
requirement in their charter.
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