by LazyJ
Based on what was discussed above, I would say yes, it is.Each ship type attacks separately from the others. Point defense gets to work against each missile volley. All the defending ships can fire at incoming missiles.
So in your case:
Cruisers attack with missiles, roll four dice, assign dice to targets, confirm all four hit after computers and shields are applied.
Defender rolls all his guns as point defense, adds computers, gets 2 hits and assigns to the incoming missiles.
2 remaining missiles hit their target. Damage is applied, destroyed ships are removed.
Drednoughts attack with missiles, roll four dice, assign dice to targets, confirm all four hit after computers and shields are applied.
Defender rolls all guns as point defense, adds computers, gets 3 hits and assigns to the incoming missiles.
1 remaining missile hits the target. Damage is applied, destroyed ships are removed.
Regular combat begins.