Bernie and Ms Warren have the assignments to make Billary APPEAR more “moderate”.
People who remember the 1990s will remember that “Triangulation” is one of the Clinton’s favorite political tactics (another being personal destruction of opponants)
In Triangulation you have like minded people move to your own extreme. This allows you to move in that general direction while portraying yourself as solidly in the sensible center.
It’s a form of incrementalism, just like people are saying here. I have no doubt that Sanders is in the race to create just such a scenario.