But the "power-consuming cloak" theory doesn't seem to be much supported by the TOS episodes, let alone the 24th century instances where cloaks basically run on two AA batteries and can be stored in a suitably large pocket.
By which time power is clearly no longer a variable since the Romulans "may have solved that problem" to quote a certain Vulcan scientist. Power is clearly not a factor as early as TSFS, so that leaves us with other reasons, namely that a less power-intensive cloak leaves room for a more power-intensive primary weapon.
Sure, the prototype ship in "BoT" always seemed to be on the verge of running out of fuel. But this could be simply because she had small tanks. There is no explicit limitation to what systems she could run at the same time - warp, weapon, shielding, cloak, comms, running lights.
And perhaps Uhura's tampons are powered by antimatter... I'm not much for speculation unless there's a REASON for it. What is the REASON to assume the technical limitations of the Romulan ship were any different from what they seemed to be?
OTOH, we're forced to speculate as to how the Romulan plasma torpedo was able to follow the Enterprise even while at warp. I would assume that disruptor weapons in general involve balls of high energy plasma discharged from a weapon emitter and launched at a target on a deflector beam or something to that effect; Klingon and Romulan ships would be able to guide the discharge by adjusting the deflector beam, sort of like a helicopter or a tank firing a TOW missile or a submarine firing a wire-guided torpedo. That alone would explain the power deficit since this type of weapon would probably require channeling full warp power to the weapon systems to move a plasma projectile that distance at that speed (and with enough destructive power to pulverize a small moon.
I'd thus still mainly concentrate on the issue that firing reveals the attacker's position, and the shot may take a bit of setting up or recovering from. It thus doesn't pay to fire unless you are sure you can do it safely, in which case there's no point in remaining cloaked and thus perhaps hampering your firing-related sensors.
If you can get within a few hundred kilometers of a starship in low orbit of a planet somewhere, sensors are the least of your problems: you're not going to miss at that range. The thing is, if your first shot is going to hit, then you'd better be sure it's going to COUNT, and that a) precludes using smaller weapons like the wingtip disruptors while cloaked and b) precludes using an unreasonably huge weapon that almost shuts down your entire ship every time you use it. I would assume that photon torpedoes can't get that powerful and neither can phasers, so that only leaves disruptors, which seem to be incredibly energy intensive super-large highly specialized weapons (unlike Starfleet weapons which are more generalist).
If power is no longer a variable (for Klingons and Romulans it still may be) then the fact that heavier disruptors require that guiding deflector beam would render disruptors unusable--or at least un-guidable--while the ship is still cloaked.
It might not require special technology to fire when cloaked; it might only require special tactics, or special daring.
I don't think it requires
special tactics, just an operational doctrine that encourages it. I reference again the difference between, say, an infantry rifleman and a special forces sniper. The rifleman wears camouflage to avoid detection, but he's also carrying an assault rifle, a sidearm, some grenades, field knife and body armor. The sniper sneaks around in this ridiculous looking ghillie suit and travels light; he carries one hell of a powerful rifle, a field knife, and a pair of binoculars.
Even infantry snipers will have equipment more consistent with the fact that they are infantry; a guerilla or an assassin or an insurgent will be traveling much lighter and probably carrying either a smaller more concealable weapon or a bigger one with more stopping power.
Chang's bird of prey can be interpreted in this light as a guy in a ghillie suit with a Colt .45. With an RPG he probably could have punched through Enterprise' shield and destroyed it completely, but that RPG is big and noisy and hard to conceal even with a ghillie suit and Enterprise would have shot him right back.
In the end, I'd suggest that the preparation for firing is usually too "energetic" to be fully hidden by even a high quality cloak, which is why most cloakship captains don't bother to stay cloaked after they heat up their guns. Chang just had a very "silent" gun and used it in a very careful yet daring manner in order to keep it hidden behind the best Klingon cloak of the era.
Nah. Chang had standard photon torpedoes courtesy of his counterparts in Starfleet, a substitute for the Bird or Prey's NORMAL weapon system. I imagine both he and some of his crew were starting to get kind of annoyed near the end that they keep shooting torpedoes into the Enterprise and the ship seemed to shrug them off and keep jinking around. If Chang had been using the standard Uber-disruptor/plasma torpedo he could have destroyed Enterprise with one, possibly two shots, but charging up that weapon in and of itself would have given away his position and he might have met the same fate as Kruge did: two torpedoes right down the throat.
So Klingons don't do sniper missions anymore, because Starfleet is just a little too quick on the draw. Instead they just beef their ships up with crazy levels of armor and pound their enemies to death, face to face. The Vorcha class can be seen as the ultimate expression of this with its big forward Macross Cannon disruptor thing.
