Ok, there is a huge information disconnect with the OP. No one is suggesting that one Honda 2000 WILL run your AC all the time. For reliable operation yes you should parallel them. This is entirely different than the issue of using a 15/20 amp shore power plug to run the air.
If you purchased the generators to run you AC at home and not install a 30 amp 120 volt rv plug you spent too much. If you purchased them to run the AC while camping just figure out what other items are on in the RV and turn them off while running the AC.
