The M code stream  might be independently attacked based on knowledge of
clipper chip protocols as revealed plaintext.  This could be invalidated
by changing the temporal and or spatial relationship of the clipper M stream
and the actual transmitted stream, under the control of a secure key
generator synchronized between endpoints.

The useful life time of captured law enforcement blocks might be limited
based on hostile forces using them as targets following transmission
interception.  You would need a large number of them, but, hey there's
supposed to be millions of these things, right?  Adding time stamps to
the encrypted law enforcement block is probably impractical, who wants
an encryption chip with a real time clock?

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The entire idea of the law enforcement block can be invalidated.

I just had the thought, that you could capture your own law enforcement blocks
for session keys K that you will not use in actual transmissions as
the session key authenticators.  The proviso that you don't mind your own
serial number being discovered.

d. denning just sent out further information of a new version of the clipper
chip.	If a hash function were to be embedded in a clipper M transmission
block reflecting the law enforcement block, it better not fall on 64 bit block
boundaries.  If it were a recognizeable datum, you could lie with it too.

I like the randomizer inclusion in the MYK-80.  I remember reading that
Intel had an approved random noise source on silicon, hence the ability
to put it Inside.