The fuel hedging techniques used by airlines are fairly complex. Marren's statement oversimplified the airline's fuel costs.
United in the past had an inept fuel hedging strategy; whoever hedged for Continental was better but it's been quite a few quarters since I analyzed any airline 10Q/10Ks.
In order for an airline to get the proper talent to effectively hedge, they really need to offer a minimum of high six figure salaries. Airlines don't pay that well so anyone who's talented is usually hired away by large hedge funds. Starting salaries/bonus of junior traders is several times higher than what airlines pay for equivalent work.