Let's say that the Player Character has a +4 in Fight. He's confident that he can take down two Goblins with a single action, so he decides to roll against both of them. The results are as follows:
- PC rolls a 4
- Goblin A rolls a -1
- Goblin B rolls a -1
PC divides his shifts in half, giving 2 shifts to each and succeeding by 3 each. That's two successes with style. Does he deserve 2 boosts?