A couple of questions from SLF...
1) What's the rationale for using less than 100% power at take off? Other than cost, is there something else? Like you're more likely to have engine failure, or the performance characteristics make it more difficult to fly?
2) Given the plane knows the start and end destination in its avionics, couldn't it at least alert a weight that would seem way out of the norms when input?
3) Given the avionics know runway length, pre-set power, and V1 couldn't the avionics suggest an abort of takeoff if the performance characteristics seemed significantly out of bounds?