Why do the Klingons use cloaking devices so enthusiastically?

^ The whole intention is to win the war. If a battle looks like it will be lost, one doesn't wish it to be a total loss and let everyone perish, especially if there's an option to retreat where a regrouping would result in sufficient reparations for a more effective engagement the next time around. However, if a particular battle is significant enough where retreat would result in those forces continuing on to reach other combat units, one would continue the battle and serve to weaken the enemy as much as possible, acknowledging that in the end, your unit will perish but the enemy will be weaker on their next engagement with other units on your side.

 

I dont think we see Starfleet using tactics either.

Usualy we see lone ships fighting eachother.

 

You can have tactics in a one-on-one engagement.

I remember proposing that perhaps the Feds agreed not to use the cloak as long as the Romulans didn't use their blob o' doom weapon from Balance of Terror. Which neatly explains why we hadn't seen said weapon since.

 

Those are plasma torpedoes, and about 7,000 of them were installed on a Bajoran moon apparently for "defensive" purposes.