Engine has sparks coming out of the back, engine shutdown......no more sparks! I would far rather fly across the atlantic on a 4 engined aircraft with one shutdown, after all the 747 is certified to fly on 3, than undertake a 3hr plus ETOPS diversion on the one remaining engine (aka US airline across the Pacific). Personally, I would say thanks to the BA crew, better Manchester than an extra night in LA!