It’s actually pretty damn smart of the Dems. They’ve realised he knows nothing about policy and isn’t going to learn, so when he negotiates with them he has no concept of what the stakes are so they can put one past him every time. He gets to feel important and make ‘a deal’, while they actually get what they want (within limits I imagine, they’re never going to con him into a carbon price or higher taxes on the rich or anything of course).
Have to admit I would never have dreamed of that tactic. You have to admire the sheer brass face of it.