Interestingly enough what Covad appears to be saying is:

If we had a way to announce two things

1 - here are the advertisements for covering aggregates for Covad

AND

2 - do not believe any more specifics for these address blocks, as they are NOT part of Covad's routing policy for these prefixes

then we would not be seeing this unfortunate case of unauthorized route leakage being resolved in a way that seems to have unfortunate bgp implications in terms of more specifics appearing.

So its an interesting question. How could Covad achieve a routing policy announcement of the form as stated in 2 above?

regards,

Geoff