As a committed CT grognard who, after trying real hard to get into MT, essentially fell back to CT w/ only a few bits & pieces from the later versions,
here is my submission;

(OK, Doug, I *know* you won't like it!)  ;-)

Note: I originally came up with this  after some PC's wanted to get into a mega-campaign of sorts while in military service.
It was about about a year before MT & The Rebellion appeared so it was long, long before SJG's GT material appeared.
This served as a  briefing/orientation hand-out to familiarize the PC's to the general admin structure of the 3I.

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My view is that the subsector government, headed by the relevant Duke, raises & runs the 'colonial'
army & naval units. The 'colonial' army units are stationed on a 'homeworld' & stay there subject to
temporary deployments elsewhere in their subsector for training exercises or maintaining order.
In case of emergency these units are subject to sector-wide deployment. An idiosyncracy of the'colonial'
army units is that they are equipped at the tech level of their 'homeworld', presumably to simplify logistics.
Thus there can be a fairly wide range of TL's (specifically from 10-14 w/i the Spinward Marches) present
amongst 'colonial' army units. The 'colonial' naval units are similarly raised, run, & stationed but they
engage in regular training cruises around their subsector. During a war they also are subject to sector-wide
deployment. They are equipped w/ out-dated IN equipment at a uniform TL14. The sector government, headed by the
relevant Duke, coordinates the various activities of the 'colonial' units w/i it's sector.

The 'regular' Imperial Army & Navy Units are, in theory, raised & run by the central Imperial government
at Capitol itself. However, in practice, & even more so since domains, w/ their respective archdukes,
are now back in the administrative picture, the sector governments are actually primarily in charge,
coordinated w/ their respective domain administrations. 'Regular' Imperial Army units are stationed on
'homeworlds' like the 'colonial' units but while they usually only exercise (reportedly for budgetary reasons)
w/i their subsector, they can be temporarily deployed thruout the sector to maintain order, etc. It's also
possible, for a 'regular' Imperial Army unit to be deployed or even, very rarely, permanently transferred
anywhere w/i the Imperium, if & when the Imperial Government on Capitol deems it necessary. This can now also
happen w/i a Domain following the recent reform of the Domains. Imperial Army units are mostly TL15 w/ a
significant fraction (about 15% w/i the Spinward Marches as of the onset of the 5thFW) at TL14. A very, very
small number are now equipped to TL16 but this is extremely rare & no units are present w/i the 'Marches at this
TL except for a few, relatively small, mercenary units of Darrian origin. The 'regular' Imperial Navy units are
raised, run, & stationed similar to the 'regular' Imperial Army units but they engage in regular cruises thruout
their sector. 'Regular' Imperial Navy units can also be deployed or permanently transferred, similar to the
'regular' Imperial Army units, anywhere w/i the Imperium. This is unusual but not unheard of, as attested to by
the transferral (completed in 1102) of all Plankwell-class BatRons from the Spinward Marches to Corridor.
'Regular' Imperial Navy units are equipped at a uniform TL15. In time of war or other emergency 'regular'
Imperial Army & Navy units can be deployed anywhere w/i the Imperium. The Imperium also maintains an empire-wide
coordination of forces, such as the 'automatic' (according to pre-established contingency plans) dispatch of
naval forces from Corridor to the Spinward Marches during the FFW, & also reviews any transferrals initiated by
the domain adminstrations.

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