Does no preferred domain allow interlinking spammers to double their output?

[RobertFisher]

Doing research on new client's links. Found 151 linking root domains all from same interlinking scam. Here are duplicated domains for one site (not my client) on his scam: DrainageHouston.com, patiosandponds.net, patioshouston.net, houstonlandscape.org, drainagehouston.com, houstonoutdoorlighting.com.

I have attached an img. showing these in OSE with each having a www and a non www linking to the site.

Note: When I found this it was by checking other domains they owned that they did not know had sites on them. They literally were all cloned with other domain names. We took the three additional sites and did 301 redirects from those to main site. Since there were only three additional and only about 30 pages per, I do not see it as a problem with redirect.

So the question is: By doing this without preferred domain and 301 in .htaccess of non-www to www, is he able to double his dubious enterprise?

[AlanMosley]

You mean he can double the amount of links that he can give from these domains, www and non www.

Yes, but the rank of them will be less because they are split, so he has doubled the links he can give but at half the value.

[RobertFisher]

Thanks again Alan, with the other issue my brain was not functioning. That was just a duh moment.