You really have to be careful about passing comments on things that you dont know about.
We had a similiar discussion about reduced thrust takeoffs from PHX, i showed UA documents which showed that over 90% of their flights were operated using reduced thrust, the % on the larger newer aircraft was even higher.
One of the takeoff limitations of modern jets is the accelerate stop, this is the aircrafts ability to accelerate to V1 or Vef (depending on certification date), suffer an engine failure and come to a stop by the end of the runway using brakes and aerodynamic stopping forces, no thurst reversers.
This isnt the only takeoff limitation, but it is one of the major ones. Its therefore extremely easy for me to say that takeoff calculations use all the available runway, all that i have to do is check the field length limit weights. But for you as an observer, you wont have seen that many engine failures at V1 when the aircraft is field length limited, so regardless of what you actually see with your own eyes in CPH, it doesnt tell you what is actually going on!
Now say that the outside air temperature is 20C, and you are doing a max takeoff weight in a B744 from JFK, that aircraft, you could find that you would be able to takeoff if the temperature was 40C at the same weight.
So why use all the available engine thrust? You can fool the engines into thinking that the outside temperature is 40C, they will therefore produce the corresponding thrust.
This policy can apply on long runways or short runways and with just about all aircraft types!
If I'm wrong, you will see the results on CNN at around 9.30 pm New York time, but trust me I hate swimming