Why would John use a "marker" with Santino?
In JW Chapter 2, we learn that John had a marker with Santino, which he used to accomplish his "impossible task". But if he was trying to retire, why use a marker? He would know that Santino could then use the marker to basically force John to do his bidding at any time in the future, and he couldn't truly 100% be out of the game with that debt looming over him. Even if Helen had never gotten sick, John would inevitably be dragged back into the criminal world...it just seems odd to me that someone as resourceful as John would be willing to have that Sword of Damocles hanging over his (and Helen's) heads for the rest of their lives together. We see throughout the series that he is capable of plenty of "impossible" tasks all on his own. I know that without the marker, we don't get the plot rolling, the only reason I can see is "because the plot says so." Thoughts?