Hey, it's popular nit, lol... the debate will continue I'm sure...
I have another Nitpick involving the difference between the Obsidian Order and Central Command-who's in charge?
In "The Defiant", Dukat says that both organizations were supposed to answer to the Detapa Counsel, but in reality they run their own affairs.
Central Command even had an observer from the Obsidian Order there, who was seeming to call some shots. She warned them not to go into a system that 'belongs to the Obsidian Order'..
They seem to be on equal footing, even overlooking the Central Command..
In Second Skin, Obsidian Order agent Entek is interrogating Kira, when her false father, Ghemor comes in and tells him to stop.
Entek tells him that it's Obsidian Order business and started to say something about their autonomy when Ghemor cuts him off ...
Ghemor tells him that the autonomy "is a privilege granted by the Central Command and is revokable at any time. Don't you agree?"
Entek starts to say something, then backs down.
If this is true, then the Obsidian Order gets its authority from Central Command itself.
Central Command controls the Obsidian Order?
Cardassian politics is...complicated. For one thing, family connections and other personal details give each individual more or less status than their position alone might suggest. The influence the Order and Central Command have over one another, and the details of their delicate power balance, are probably constantly shifting. Every Cardassian no doubt has half a dozen means of exerting influence over his or her rivals, and simply waits for the best time to use them. Perhaps Ghemor was saying "since Tain left not too long ago and the Order has a new leader, things aren't quite settled yet. If enough members of the CC (among whom I have high status) make a fuss or call in their favours or set in motion their long-term plans RIGHT NOW...well, maybe the Order might have to...give way somewhat?" Maybe calling the Order's autonomy a "privilege" is simply a threat, not an actual legal reality. The "don't you agree?" comment makes it seem more like a negotiation than a statement of fact.
The Central Command and Obsidian Order are technically under loyalty to the Detapa Council, and its laws, but while the Council and the Civilian Assemblies maintain control over the budget/funding and such, and so can still exert
some influence, Central Command and the Order have gained so much power they more or less do their own thing, as you say. Given the Cardassian respect for law, I doubt the CC or Order would ever consider actually getting rid of the council, even though they in practice grew more powerful than it and really work outside of its oversight much of the time. The Council is largely toothless, a body that mostly just serves as a balance between the Order and the Command, running the day-to-day business of finance, etc, without really exerting any true power. Central Command is more or less in charge in practice, while the Order, as the intelligence service/secret police has the power to investigate Central Command (it was established on DS9 CC officers are not immune to Order inquiries). Even if Central Command does have authority over the Order, the Order can hold its own by virtue of having eyes everywhere and authority- indeed, a mandate I imagine- to monitor the military. We know high ranking Command officers like Ghemor can turn off the monitors without fear of reprisal, but of course that doesn't mean the Order isn't unofficially still monitoring...The Command and the Order don't trust one another, it's as simple as that. The Order can send overseers to Command projects, as you say, supposedly to protect their interests and keep the projects safe but also in practice to try and sabotage anything they don't like. They are not permitted military equipment, but that didn't stop them...
Until Dukat, I don't think Cardassia ever had a single leader, it's far more complex than "this person or agency has clear authority over this one". As mentioned, technically the Detapa Council is in charge but were a member of the Civilian Assembly to stand up alone and try to demand the Order or Command stand aside, no doubt he or she would very soon discover a previously unknown allergy to something in his/her drink and sadly expire...