No, actually what dominance would be defined as placing no lower than 2nd in any pro show entered, winning 6 Olympias with 4 straight firsts (something Coleman wasn't able to do while winning and beating out some of the prime bb'rs in the history of pro bodybuilding, ala Dorian Yates.
Heath competes once a year and beat an injured Cutler like Cutler beat an injured Coleman. Not exactly dominating anything except the toilet paper roll.
Heath's career isn't finished yet. For what he's done to date, however, I'd say that's dominance. He turns pro his first try, wins two shows his rookie year against top-10 Olympia talent. His lowest placing was 5th (at the two biggest shows in bodybuilding, only because he was off, condition-wise).
Heath won the big one, defeating a two-time ASC champion and two Mr. O's in the process, who were still contenders. As dominating (at times) as Yates was, the only former Mr. O he'd beaten was a washed up, quotation-placing, Samir Bannout.