this is it, Tribe’s got it:

The point would not be to take old-school House impeachment leading to possible Senate removal off the table at the outset. Instead, the idea would be to build into the very design of this particular inquiry an offramp that would make bypassing the Senate an option while also nourishing the hope that a public fully educated about what this president did would make even a Senate beholden to this president and manifestly lacking in political courage willing to bite the bullet and remove him.