His speech is that of a man permanently stuck on the cliff edge of a breakdown but by force of his hateful strength, manages to hold it together just enough to keep who he needs to go along with him (even this has been pushed over the limit several hundred times) you see it when he's in a board meeting, constantly talking, filling any voids where doubt could seep in. Like the worst desperate comedian grasping at the air with words, all the while trying to appear calm. A never ending juggling act.
Those facial expressions are someone trying to appear like they're fine. In control. They're him imagining what it feels like to be confident, and trying to project that out. Unaware of or at least blocking out how it looks from an honest perspective. Seeing that it works on enough people in front of him, he keeps at it. It's like an emperors new clothes fake it til you make it. Except he never makes it. The plates need to keep spinning.