Pin,
I agree, CAP 360 part 2 has allowed it for years. However, goalposts have moved. Mechanics have now to have a Cat A licence to carry out these tasks, pilots do not. 145 stipulates a certifier has to be licensed under JAR 66 A, B1 or B2 to issue a CRS so why shouldn't pilots? I think the idea of a basic qualification for limited/simple tasks is a good idea - it should be applied in all cases.