Sometimes in battles, Captain Picard or another senior staff member orders deception: vent plasma, for example, in order to make it appear as though significant damage has occurred to the ship. I believe such a ploy may have been ordered in "Gambit," but I'm not certain. Is such deception considered dishonorable amongst Klingons? Wouldn't they rather go out fighting?
Deception is an acceptable strategy in warfare for honorable Klingons.
The earliest example this on Star Trek: The Next Generation is in the first season episode "Heart of Glory" where we were presented with two Klingons rescued from a badly damaged freighter. During their debriefing:
KLINGON1: Our only chance was to trick them [the attacking Ferengi] into lowering their shields.
KLINGON2: We reduced power and lured them in.
KLINGON1: They suspected nothing.
KLINGON2: Then, when they lowered their shields to beam over a landing party, we opened fire.
In the second season episode "Peak Performance", Riker tried to recruit Worf to join his team in upcoming wargames.
RIKER: You're outmanned, you're outgunned, you're out-equipped. What else have you got?
WORF (considering for a long moment): Guile.
Although it has to be said that Klingons tend to display an enormous amount of hypocrisy when it comes to 'honourable' combat (preferring to sneak up on their enemies under a cloak, attacking weaker opponents without provocation, etc), it's pretty clear that they view a frontal assault as more honourable than a sneak attack but that a clever deception against a superior foe is also acceptable since it results in an evening of the odds.
In DS9 : "Blood Oath" Jadzia suggest that when facing insurmountable odds that they should consider an alternative and more sneaky assault. Kang, the D'har master immediately recoils at the suggestion.
DAX : Doesn't it? If we accept that he has adequate defenses, with a minimum of fifty guards, then we ought to use a N'yengoren strategy.
KANG : No!
Kang rises, raging... pacing... inspiring.
KANG : I will not sneak into his bedroom and murder him like a kah'plakt. I want him to see us coming for him.
On the other hand, Worf (in TNG : "Way of the Warrior") makes a pretty good case that deception would be a viable tactic.
WORF : It is likely there are cloaked Klingon warships in the vicinity, lying in wait.
BASHIR : Doesn't sound very honorable to me.
WORF : In war, nothing is more honorable than victory.
Echoing @KyleJones' answer, the most telling exchange is probably in TNG: "Heart of Glory" in which we see two Klingon warriors recounting the tale of their recent success against a Ferenghi ship. Not only do both soldiers tell the story with glee but it's notable (in relation to your question) that Worf also makes approving noises about their strategy.
KORRIS : Yes -- all we had was an ancient battery of Merculite rockets. Our only chance was to trick them into lowering their shields.
KONMEL : We reduced power and lured them in.
KORRIS : They suspected nothing.
KONMEL : Then, when they lowered their shields to beam over a boarding party, we opened fire.
WORF : Your strategy was very sound.
Moving down the canon scale, whilst leafing through an old Paramount Licensed Star Trek RPG (Starfleet Intelligence Manual : The Klingons) I found this snippet of info about Klingon starship tactics.
Klingons seem to prefer outright combat but aren't averse to using trickery and deception (in warfare) as long as it's in the name of luring the enemy in.
Understanding strategy and tactics, no. Looking weak where you are strong, looking strong where you are weak is as old as Sun Tzu (probably older in Klingon). It is the responsibility of the warrior to understand the true situation and not be deceived.
Taking this out of context / universe, in fantasy worlds where a race cannot lie (Fae in many worlds), the non-liars are the least trustworthy as they excel at telling the exact, literal truth while letting the other party reach the wrong conclusion. That is, there are FACTS (they vented plasma) and TRUTH (they are not damaged). Just because an opponent wrongly interpreted the facts does not bring dishonor on you.
In fact, we extol the virtues of the ones who can see the truth visible in facts that others miss (e.g., Sherlock Holmes).
In supplement to Richard's answer, in the DS9 episode "Sons of Mogh", Worf tells his brother Kurn that he believes the Klingons have been placing cloaked mines. Worf wants Kurn to help find out where the mines are located.
KURN: You want me to turn against my own people? Will my dishonor never end?
WORF: It is their actions that are dishonorable. Secretly mining star systems is not the act of warriors. They behave like... like Romulan cowards!