I work for a career college where are syllabi are written by other people. On the one hand this is helpful because it clearly lays out the objectives they are seeking to cover, but on the other hand it is necessary to make constant adjustments to the syllabus to accommodate the differences in classes and paying attention to their individual needs. I find myself using the syllabus as a guideline more than as a road map. I don't want to downplay its importance but I also trust my judgement once I have taught a class a few times to anticipate objectives that need more time or less time.