Although you definitely have valid points in the rest of your statements, I doubt very much this particular statement is what intended.
Truth be told, neither do I, but until I learn to read the minds at
or hear otherwise from them I can't really rule it out.
My own take on it is that the GTVA operates "mobile" fleets lead by a single frontline destroyer. The destroyer is backed up by a number of cruiser-corvette striking forces (three or four) each lead by a corvette or two and having two to four cruisers (sometimes more). Vasudans do things their own way and their battlegroups are lead by a single frontline destroyer which counts one to three corvettes and three to seven cruisers in escorts. These reflect the peacetime TO&E. Wartime obviously can cause these numbers to change as they lose ships or are reinforced.
Older destroyers, and many other ships, are assigned to the "fixed" defense forces of individual systems where they and the other ships so assigned operate more or less independently, because that is a more efficent arrangement for their usual job of guarding widely dispersed civilian assets and traffic. In time of war, they can be called on and moved up to the front lines where they are seconded to an existing fleet structure on an as-needed basis. In this way a fleet in a combat zone may have multiple destroyers in its command structure, but usually they try to add on more of the striking force units rather than overstrength the ones they have. The Vasudans don't even bother. They just let the battlegroup get as big as needs to be, since it's intended to be more or less a blunt instrument while Terran fleet organization is designed for tactical and grand tactical flexiblity.
(It's based on my idea of a sort of lessons learned from the T-V War; Terran fleets had most success with a blunt force trauma approach since they tended to have superior ships and weapons, so a straight-up confrontation worked well for them. The Vasudans usually had to do things the opposite way to be successful, though blunt force came through for them at a couple of key points with the Typhon. Rather then construct their post-Great War fleet units to do what they already knew how to do, both chose to construct them to do what they had not done well in the T-V War, to put armor over their weaknesses rather than build on strengths that didn't serve them very well against the Shivans. The hope is that a more balanced approach will result in fewer casualities at least.)