Curriculum policy could be the force to drive or destruct the curriculum innovation. In the critical period, the right policy can improve the existing problems, to carry out a new phase. However, the wrong-timing policy would bring troubles. With the implementation of twelve-year compulsory education, the ministry of education started to revise the curriculum guideline in 2013. The new guideline proposes the vision of “the adaptive education to achieve talent development”, and the idea “key competencies” to guide the grade 1-12 curriculum toward coherence. In spite of the great ideal, due to the wrong timing, the action of revising curriculum guideline opened the battlefield of subject hours, and blurred the direction of education innovation. This article indicated that the large-scale curriculum reform may not be the best policy in the conservative education field. The piece-meal innovation engineering may incrementally improve school curriculum and teaching.