Don't forget the engine/combo value you are denying the enemy by dealing that much damage in 1 turn. I believe this 1card/coin combo is worth on average more than 45 points. And it doesn't need to be a finisher, you can pull it anytime you see the enemy is building up something.Just a quick math about DJ. You have 9 coins limit and, say, 11 charges by third round (which is on average very much achievable). That is in total 20 coins, or 20 points of damage in just one turn + the 4-point body of Ewald. Now, if we add bounties to this mixture, the situation gets even scarier, because bounties are basically additional damage for free. You spend coins to get more coins to deal more damage - the broken loop.
Example: assuming DJ saved all his charges to R3 and placed a single bounty on a 6-point unit, results in a 30-point finisher. That's just... I don't know.
For 1 card.
For 8 provision.