And a third voice of concurrence. I believe that I spent a few days in hot water some time ago after our FAA Principal Ops Inspector told me that I had to fly the fixed speed schedule in the event of a diversion, and I rather pointedly told him he was dead wrong. It really depends on how much fuel I want to arrive over the ETOPS alternate with, and how low I want to go in the event of an engine failure. One of the biggest concerns is how much time you spend in ice and how much of a penalty in single engine ceiling that extracts. Faster speed may mean a higher TAT and no ice while at a very low altitude, while a slower speed may mean a below freezing TAT while above the ice nearly al the way there. Of course, if you can't get the TAT high enough, you may be speeding along IN the ice. Lots of variables, which is why the final decision must rest with the operating crew.