Hi, clarifying question on the Combat Complication: "Characters take +2 to their Attack Roll for each other person striking the same target."

Ignoring any other Attack Roll modifiers and just focusing on the Complication above, if PCs 1-4 are all attacking the same target, would it look like this during the first round:

PC1 attacks and hits, striking the target.

PC2 attacks with a +2 because PC1 struck the target, but they miss.

PC3 attacks with a +2 because PC1 struck the target, and hits, also striking the target.

PC4 attacks with a +4 because PC1 and PC3 struck the target.

Then the next combat round this all resets. Does that seems correct?

at my table i would ask how many people are attempting to attack the single target and share the bonus - so if three people are trying to hit the same target, they all get +6. this resets each round. 
the idea is defending yourself from multiple people is very difficult - so go with whatever gives that impression best for you and yours. 

SPOILER WARNING FOR GRAND CAMPAIGN

Thanks, Luke! My group just played our first session and we discussed how to apply the +2 to hit before we started playing, and decided to use the same approach that you outlined in your response. The four PC party brought some of the former thralls into the dungeon at location 29.08 and they absolutely destroyed the purple worm in like three combat rounds because each attacker had a +18 to hit in the first round and they took away over half the worm's HP immediately. I was reflecting after the session and I figured we must have misunderstood the intent of the rule. A to-hit bonus of that magnitude made the combat seem like a forgone conclusion, but I suppose that's the benefit of bringing a large party to concentrate force on a single target. The worm did eat four of the former thralls though! Love the game, and I'll probably have more questions.