syncronising ship movemnt in Simultaneous

[Roanon]

Basically correct, Wildcard. Minesweeping happens DURING movement, while each individual fleet moves. Combat happens after each movement "day" of the turn.
So if you syncronize fleet movments (by hoping that shift+click actually works or by mixing ships in a way that fleets have same speed), you have no problems combatwise. For minesweeping, it is difficult or impossible to determine which fleet will move first each day.