TIM is a xenoracist. But he's a high-functioning xenoracist. He dislikes aliens and he wants humans to be on top militarily, economically, culturally, and politically. And he wants to be in charge of humanity, behind the scenes.
The whole 'liason with the Asari' thing.. it's a transaction. He's getting something out of it personally, and he's manipulating the Matriarch in some way. TIM has multiple layers of plotting and plans in action.
Just look at the whole game of Mass Effect 2. He's conspiring with the Collectors to give them Shepard, while at the same time using Shepard to thwart the Collectors. That attack in the first few minutes of the game? Who do you think leaked the Normandy's patrol routes and operational area to the Collectors?
Each time he tips the Collectors off, he gets a piece of their tech. So that in the end, even if Shepard denies him the Collector base, he's got something to show for the effort AND working duplicates of the Reaper IFF so that he can have his ships pass through Omega-4 safely to loot the remains of the base.
He's in control of himself enough that he doesn't feel the need to spout crap to make himself feel better about it.