Just researched it. GSP has indeed won every single round since regaining the title and had some 10-8 in there as well. He won 4 out of 5 via unamous decision scoring 50 on each score card and won all 3 rounds vs Penn before the stoppage. Thats not against chumps either. That's Fitch, Alves, Koschek, Penn, and Hardy.
That's just sick.