In other words, Dayman isn't sure if he can tie the spam to the spammer. And ironically, despite his doubts, Dayman is closer to winning that game than he realizes. At least he's caught some personal information. Most serious spammers manage to completely avoid giving up such data, say systems administrators. Indeed, several options are available.
Speed is one.
Many spammers send thousands, even millions of e-mails from one address, then shut down quickly before someone like Anderson at Redshift blocks them, or before they're added to MAPS Realtime Blackhole List, which blocks all mail coming from ISPs that have allowed spammers to use their networks and going to networks run by RBL members. Others fake their identities. And if it's not an international address they're sending from, it's often a stolen one. Dougherty doesn't think so. On the other hand, Dougherty would be happy to put the professionals out of business.