no because everything on the "net" is circumstantial and speculated, even an IP address.
the only way to be confident the information about a certain subject on the net is 100% accurate to the subjects self, is by validating the origination of the subjects information by substantial fact and proof and this is only accomplished by access to a federal/state warrant.
for example, just because you know my IP address does not mean the geo-location from it is my actual or nearby location, it also does not mean the subscriber of that IP address is the same individual using it and unless proof of a crime being committed using that IP address can be substantially established, you're not getting this information.
hence, the FCC can't possibly, legally and factually establish a definitive connection between an IP address and a pirate radio operator and use this information as a means to send NOUO letters or as a "guide" to locating a pirate.
the FCC cannot obtain a warrant on an IP address for further information simply based that the IP address was "associated" with a posted comment related to "illegal" activities because it could be anyone, even someone pretending to be someone else.
it's not like file sharing where IP addresses are connected with each other and files are accessed, that's solid proof.