Why is he commanding the fleet from a Defiant class ship?
Since commanding a fleet from a
Defiant class ship is clearly not going to be easily explained away, I think it worthwhile to challenge the other half of that question...
Sisko was asked to
plan the operation to retake the wormhole (and, if possible, DS9 as well). Not necessarily an unrealistic job for a Captain who is already pretty deep in the loop. And then, at reaching the Bajoran system, he was given the honor of saying "Go!".
But did he actually command the fleet
beyond that point? After the battle was joined, he gave all sorts of orders and asked all sorts of questions, but those would be valid things for the commander of an individual starship to do, too.
Sisko gives orders to attack fighters - but several other starships might command their own formations of attack fighters as well. Sisko worries about other ships being "too tight", but then fails to give orders to those ships, and instead again starts giving orders to attack fighters, at which point jamming prevents communications.
When we next see Sisko, he isn't talking to anybody - but is operating in concert with two
Mirandas, suggesting the comms jamming has been defeated. Then those "wingmen" are lost, and Sisko immerses himself in a single-ship fight, not giving any thought to the fleet beyond this point.
We can
almost claim that he never had command of the fleet to begin with - that he only had a pre-formulated plan of harassing the Cardassians with fightercraft, and the authority to say symbolic "Go!" on that plan, at which point the Admirals in their
Galaxy class ships would start managing the battle.
Almost. There's one reference to Sisko giving orders to "destroyer units" even after the plan has already been pushed past the no-return mark, and a guy in a humble escort should at most have the power to humbly ask for help from destroyers...
Timo Saloniemi