Short answer: No
There is little point in blocking the access of an external IP address of your computer. It is YOUR IP address that is the important one that is of interest to copyright holders. The use of Peerblock does not prevent your IP address appearing in the list of participants in a bit-torrent download.
Peerblock and PG2 ONLY BLOCK IP addresses that are on a list. They mearly block the access of traffic to and from that IP address. If you are trying to access an address on the list you will be blocked. However, the owner of an IP address on the list is unlikely to be even attempting to access your computer. So there is little point in blocking it.
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