Value of combined unit direct fire

[XLVIII Pz. Korp]

The advantage of firing singly; a single round may cause a retreat which makes the target vulnerable to susequent shots taken against the rear target aspect, or firing one vehicle alone may achieve a desired result leaving the remaining unfired vehicles with full AP's for follow-up or exploitation of the result

Disadvantage of firing singley: the first shot may unleash a torent of op-fire potentially targeting everyone in the MK IV hex, leaving you with a hex full of disrupted unfired units or worse wrecked ones.

Mathematically, there is no difference at all as the system executes one seperate combat resolution for every strength point that fires be they combined or single.

Really the tactical situation should be the determining factor.