Quoted Text
Blaster,  why would you add the decks later? 
 Harm
A lot depends on your approach and your equipment.  I have a light/magnifying glass on an adjustable stand, as opposed to glasses that I wear.  That somewhat limits my viewing/working space.  I probably spent about 6 months working on just the center section. I made a deliberate trade-off decision to not glue that to the hull for a couple of reasons.  
The first was that it would have made trying to get just the perfect angle under the glass just about impossible, trying to move the entire hull around.  It's too long and cumbersome.  And I plan on placing the finished model on a wood plank base, and not piercing the hull, so a fixture wasn't what I wanted to do.  And handling the hull for 6 months would have probably had a significantly detremental effect on the paint job. It was a lot easier working with just the deck section.
I'm sure I'm going to have some "issues" when I mount all three finished deck sections to the hull, with filling seams between the deck and hull and the deck pieces themselves.  And I've already resigned myself to the fact that I'm going to have to do some touchup, and that part of the build may not be as good as I'd like.  
The foredeck is going to wind up being done as installed for a different reason. The biggest reason is because the structure around the forward 20mms needs to be not only seamless to the hull and painted as one unit, it has to be on top of the foredeck.  And because the deck blue stain on the foredeck has to go far enough underneath it to make painting that AFTER assy not practical, I have to paint the deck blue first, secure that to the hull, then add the "bull nose" , and then mask off the painted deck section to paint the forward part of the hull in haze gray. 
For that section (and there is nowhere nearly the amount of detail work), I'll detail after it's installed.  I don't know if that's the best way or not, but it's the best way that I could come up with.
I think it really comes down to what works best for the individual.  And the sequence could easily be different depending on the construction of the ship and the amount of detail to be added.
Tom