I just found this post, it will help you understand why one can easily mistake CRS tool in this case, its mentioned "experience in only one occupation" there and that is what confuses most people as they have not mentioned there anything else to further clarify. They should make it more clear there, that was being discussed here. If we go by English language it means strictly one occupation which most people consider means NOC and is logical in that sense, though this contradictory and not true completely.
Link-http://www.canadavisa.com/canada-immigration-discussion-board/threads/foreign-work-experience-under-multiple-nocs-skill-transferability-crs.386975/
Link-http://www.canadavisa.com/canada-immigration-discussion-board/threads/foreign-work-experience-under-multiple-nocs-skill-transferability-crs.386975/