You gave the only statistic that matters - US is proposing the least capacity, except for AMR @ 245 seats in 3-class configuration and Maxjet @ 96 seats in all-business class configuration. Presumably, if US thought a bigger airplane was needed it would have been in the application.......
Jim
You're statement is a little misleading. I would say that the capacity that US is putting out there is fully in line with the other capacity being offered.
2007 Frequency:
Delta at 268 seats in a 777-200ER with "minimal" cargo westbound and 17,000lbs of cargo eastbound (then later moving to a 276 seat 777-200LR)
Northwest at 403 seats in a 747-400
2008 Frequency:
United with a 258 seat 777-200ER
2009 Frequency:
American with a 242 seat 777-200ER
Continental with a 283 seat 777-200ER
Delta with a 268 seat 777-200ER, with 9,000lbs of cargo westbound and 20,000lbs eastbound (moving later to a 276 seat 777-200LR)
Northwest with a 403 seat 747-400
United with a 347 seat 747-400
US Airways with a 269 seat A340-300 (Cargo: summer months 22,500lbs of cargo westbound and 17,200lbs of cargo eastbound. Winter months 23,200lbs of cargo westbound and 20,000lbs eastbound)
So during the year that US is bidding, they will offer more capacity than American, initially 1 more seat than Delta, then later 7 seats less than Delta, and 14 seats less than Continental, but then a big gap lower than NW and UA. But since there are 4 slots in 2009 up for grabs, even if capacity was an issue to the DOT, slots given to UA and NW based on capacity would still leave 2 slots to carriers who are basically all offering the same amount of capacity.
EDIT TO ADD:
Also note that the A340-300 will offer the same exact seating configuration as the old A330-300 seat chart. It will have the Envoy Sleeper section, the same amount of regular Envoy seats, and the same Economy seats. And the A340-300 is the same exact length and width as the A330-300. So that means that US will be offering the most room in economy, with the old 33-34" pitch in economy. AA offers 32" in economy. CO offers 31" in economy. DL 31-33" in economy. NW 31-32" in economy. UA 31" in economy (they have E+ with 34-36"...but you pay more for it.