@BK613 - Like I said to Timo, if Spock had not confirmed the location after Sulu was told to target Nomad then I'd agree that the ship was turned to bring her forward tubes to bear. (And yep, Sulu was ordered to take "evasive maneuvers".)
But, the order of operation was:
1. Enterprise maintaining Evasive Maneuvers
2. Location established by bearing and distance. If the Enterprise is still turning and dodging and the bearing and distance doesn't change it indicates Nomad is deliberately staying at that bearing and distance from the Enterprise irregardless of what Sulu is doing.
3. Sulu ordered to target Nomad. He's got plenty of time to turn the ship before the next order.
4. Spock confirms that the target location (bearing and distance) is holding steady (no change).
5. Kirk orders fire on target.
1. If Sulu was continuously maneuvering and Nomad was holding same bearing and distance, then there was no way they could've turned to hit it.
2. If Sulu could've turned and Spock confirmed a new bearing then it would indicate a turn to bring forward tubes to bear but that wasn't the case as nothing had changed between them and the target.
And a separate episode, "Elaan of Troyius" showed us that "all tubes" only as forward facing tubes.
Under other conditions, I'd love to add a stern tube but I just don't see it based on the parameters that we're given from the episodes, IMHO. (And it doesn't help that the later movie Enterprise clearly is lacking stern tubes in it's design.)