something that no one has discussed yet (or I missed it):

The FBI sets up a wiretap AFTER the court order was handed. 
Only at this point they can access the line and detect 
the serial number N.

What happens next, does the FBI simply asks for the keys
for N, and, since a warrant was issued for the line, the FBI 
simply gets it? What if multiple phones are used from the
same house, the FBI just asks for N1, N2, etc.?

Exactly who is to prevent the FBI from claiming some
other serial number, X, was also used over the wirtapped 
line and get the keys for X? 

Either a second court order (for the specific serial/key)
is required (and I have seen no indication of this), or
the FBI can effectively ask for any pair of keys at any
time, so the escrow key holders are a total fake.

An unrelated issue: if and when all phones always use
the clipper chip, how are call-transfers going to take 
place?!
