Why superships cost more per mass

I'm going to point out something I haven't seen 
anyone mention. The issue of system 
complexity. A larger system is a more complex 
system and this applies in pretty much any area 
of engineering. A large ship has the same 
problems a small ship does, but not just on a 
larger scale. It has an increased level of 
interconnectivity between combat systems, it 
has a whole raft of problems never seen in 
smaller ships which mean more engineering and 
possibly more expense to solve (often differing 
systems), and it has to not only be more costly 
in proportion to its increase in mass, but 
probably in proportion to a power of the 
increasing mass. Anyone who has worked on 
systems on small vessels and large vessels, or 
on small planes and large planes knows that 
some of those systems need to be scaled up 
and the increase in complexity is not linear. 

Additionally, I suspect shipyard space, even if it 
is orbital, increases in cost at more than a 
linear cost. Maybe less so than in aquatic 
equivalents, due to the difference between orbit 
where I can slap similar yard modules together 
and the ground where I need a bigger slip. But 
there is still an increasing number of personel 
involved and coordination on these projects. 

Anyone who has worked for IBM, Sun, Mutual 
Life, etc. (or the army) will realize that as your 
work force gets larger, management increases. 
Not just in numbers, but in levels. You get 
middle management. You get more overhead 
per person. This isn't just waste, it represents 
the difficulties of coordinating large worker 
pools. Also, as you get these larger groups, a 
screw up by one person or group holds up a 
larger number of people and hence costs more 
than on a smaller project. Hence your large 
ship constructions will run longer and cost more 
just due to organizational complexity. 

Must this be the case? Hmmm. I don't think we 
have one good example of where it isn't. This 
relies more on the nature of large complex 
electronic, mechanical, and human systems and 
organizations than it does on the particulars of 
making any one subsystem (such as a beam 1 
or beam 4). It is _possible_ that you could PSB 
away these problems (or characteristics), but I 
don't think this has been historically supported. 

All one has to do is look at the Canadian Navy's 
relatively modest effort to construct 12 frigates 
and how badly cost overrun and delayed some 
of the systems have been (anyone heard of the 
HMCS Ville De Quebec?) to illustrate the point. 
These are not huge ships. They aren't terribly 
more complicated than many smaller vessels. 
They (if the people who believe in cheap large 
projects and scaling linearly with mass are 
right) should have been constructed far sooner, 
with far fewer problems, and with far less cost. 
It didn't happen. This is only ONE example of 
this. Many exist. 

The other thing is, on large scale projects, 
despite people making derisive noises, the 
costs escalate due to the Military Industrial 
Complex's billing and project management. On 
larger projects, managers fear larger looming 
unknowns. (This applies to construction of a 
known class almost as much as to construction 
of a new class - note that rarely are two ships 
of the same design truly the same due to 
continous upgrades during construction which 
throw wrenches into things and these are 
consistently occuring). So they budget in not 
just more gross amounts of time, but more 
percentage wise. This also tends to increase the 
profit margin, because that is a factor applied 
to the overall budget. So if the budget goes up 
due to complexity or schedule fears, and if 
penalty payments and stuff go into it, and profit 
is a percent of that, the whole gets more 
expensive in a not-linear-with-mass way. 

It isn't that it isn't (theoretically) possible to 
construct large ships in an automated assembly 
line fashion for a proportionate-to-mass cost. It 
has just (AFAIK) been not done yet, or if so, 
done a heck of a lot fewer times than the other 
option (disproportionate-to-larger-mass costs). 

Ultimately, this comes down to doing what you 
want. The costs in the game are not quite right 
for one off combat, and work for small 
campaigns. They probably aren't great for large 
scale campaigns (strategic games spanning 
years or decades), but they were never meant 
to be. In general, they balance (mostly) against 
one another if you use FB ships. If you design 
your own, you'll have to apply good sense to 
realize where the system is likely to break. 

Caveat Emptor.