So, our DM came up with a Motivation System. At the Start of the Session you start with 0 Motivation and gain or loose it at a rate of 1d6 if something good or bad happens in the fiction. Every +/- 5 points of Motivation you gain a re-roll token if you have positive points, or the gm gets one to force a re roll if on the negative scale.
To say the truth, im a bit skeptical, i said ok, lets just give it a try and see how it works.
What do you think about re-rolls in DW ( or this Motivationsys I outlined)?