Since no-one else has picked up on this, I come back to a point raised by mig3: "use of reduced thrust on take-off - noise abatement".
I may be (I am) out of touch, but I can't remember take-off thrust routinely being influenced by noise abatement. Cut-back is another thing, but start-of-roll?
Not only that, I think it could be counter-productive, as it's best to be as high as possible over the measuring point. Comments?