The crucial choice for any attack through mass relays is how to divide the fleet for transit. The accuracy of a relay's mass-projection depends on the mass being moved and how far it's going. Any long distance and/or high mass jump will see "drift". That is, a ship may be hundreds or millions of kilometers from its intended drop point, in any direction from the relay.
Distance can't be chosen by admirals, but a relay is told how much mass to transit. For example, if told to move a million metric tons of mass, the relay will scan the approach corridor, find four 250,000-ton freighters, and transit them together, maintaining their relative positions.
A commander has the option of moving his fleet as one large, coherent formation that may be wildly off-position, or breaking it up into many smaller formations that will be individually closer to the intended attack point, but could be widely dispersed.
Conservative assault doctrine holds that fleets should be moved en masse, maintaining concentration of force and reducing the chances of collision. The only time it is reasonable to split up a formation is during blockade running.