I like this new Vergil, some are saying he's to soft but I think it's all an act.
At the end of the trailer he tells Dante they have to trust each other without hesitation which could mean he doesn't want Dante questioning his motives but why???
cause he's evil!!!!
dun dun dun
...
or he says that because Dante's new to this whole brotherly love-team work thing
I'm pretty sure he says that because he actually needs Dante's help, and not to control him. Dante is the one who asked that they rescue Kat, at the risk of the mission (and therein, all of humanity), so, Vergil said that "I'll do it your way, but you'll have to back me up and trust me completely (let me take the lead) 100% on the battlefield. Because, while Vergil may seem like he doesn't care about Kat, he does, but he can't put his goal at risk, either. So, he asks that Dante let him lead.
That's all it is. If there is an 'evil villain twist', then, oh well. But, I really hope that that is not the case.
Oh, and your name reminds me of this joke from Two and a Half Men. Alan's mother says to Alan, "I can't believe that guy (Ashton Kutcher, the worst thing to happen to the show) let you live here. You're like a human barnacle."
I laughed so hard when I heard that. I still laugh at that joke, sometimes. XD