8che -
First off, 30 seconds at reduced thrust on a departure so the mechanic can walk out there and keep signing off blades that 'don't look that bad' is the reason why you put thousands of feet of runway behind you and climb out over the bushes every day is hardly a sales point for 'safety first'...
That said, as far as 'efficiency goes'...just because an engine can burn hot doesn't mean the fuel flow is going to make it to Hawaii.....