I picked up the idea of a 3 round campaign from the BattleFront: Kursk Campaign and the BattleFront: Campaigns in Flames of War page on the Battlefront Miniatures website. Essentially it is a serious of linked scenarios, with some pre-determined logic for which scenarios are fought depending on the results of earlier games.
The 3 Rounds
Generally speaking the three rounds are:
A battle is fought in each round, and the results of earlier rounds dictate the scenario to use in later rounds. That means round 1 is always the same scenario. The scenario to use in round 2 depends on what happened in round one. Similarly the scenario to use in round 3 depends on the result of round 2.
It is easiest to show this progression in a chart:
7 Scenarios, 4 Paths, 8 Results
As you can see from the Campaign Chart there are at most seven possible scenarios in a 3 Round Campaign. There are four possible groups of scenarios and eight possible results. Of course only three of game will be played in a particular campaign – one for each round.
For simplicity casualties should not be carried between rounds on the assumption that reserves are fed in as front line troops become exhausted.