I think you misinterpret the use of the word dominant as its beeing used here. Christiano is great no doubt but not a dominant type of player in terms of the use of the word in this discussion.
Messi is/was though.
For many years now it has been my opinion that Messi is the only player today that compares with Ibra (or the other way around), CR is not really in that discussion. He is awesome in his own way, but he doesnt carry teams, he doesnt carry anything. He scores the 4-0, 5-0 and 6-0 goals, and when things doesnt go his teams way he cries (the loudest) with the team rather than takes the initiative.
But what Messi did some years back, that was pure domination, sometimes beating the world by himself. Ibra definately has had dominating performances like that, but not against a strong United in a CL final. At least not yet.
On the other hand, Ibra has the ridiculous things never seen on a fotball field before, the inhuman amount of impossible kicks and flicks. I think he and Messi is comparable in the way they are both dominating completely, and they both do it in their own unique ways.