French battleships can make 22.8 knots while the campaign battle line makes 21, so the fleet divides into fast and slow wings. The battlecruiser and light cruisers can both overtake and outfight the opponents in this particular engagement, which lets them hunt while the slower battle line follows. Dividing the force keeps the faster ships from being tied to the slowest hulls. The exact speeds belong to the scenario, but the underlying problem is historical: pursuit and concentration depend on the relative speed of opposing formations.
Notable Point · 12:23-13:09
Fast and slow wings preserve different tactical strengths
The campaign separates a 21-knot battle line from a fast wing of battlecruisers and light cruisers that can catch and overpower the opposing force.