Why would you add another procedure - changing the CLB thrust - at 3000' if you don't have to? There is enough flying to do at that point that you don't need another distraction.
The SOP quoted by the OP doesn't make sense for noise OR safety! A lower CLB thrust will keep you closer to the ground for a longer time and distance. So if you need full CLB instead of CLB1 or CLB2, program it from the start!