Actually tinyrice, he isnt pulling your chain, we have operated Classics for years with packs off for this reason, we have the option to do it on the 744, in these cases the APU is used to supply cabin air. We will soon reintroduce Pack Off takeoffs on the 777 in order to carry around 27 more passengers, but as the APU on this aircraft is not approved for use during takeoff, the passengers will have to melt ......
Cheers
Mutt.