Thanks,guys!but it is still confusing,
the purpose of improved climb is to use excess runway to get higher V2 speed,so we can still get the 2.4%climb gradient at 2nd climb segment with greater weight.we should notice that the method is designed to meet the regulation requirement at 2nd segment of climb,not the obstacle clearance requirement.At some high elevation airports with high terrain,if improved climb is used,the new weight may exceed obstacle limited weight,that's the problem.
