As Saleh al-Ajmi clasps the antiquated little red wheel on oil well B473, the vast, dusty expanse of the world's second largest oil field unfolds behind him.

"I love Burgan," the Kuwaiti engineer says with a pride and tenderness usually reserved for girlfriends, not oil fields. But Burgan has earned his devotion. It is perhaps the world's best-behaved reservoir. It has produced more than 28bn stock tank barrels of oil in the last 60 years with only minimal investment in new technology.