Я тут прочла любопытную мысль:
http://www.ftponline.com/javapro/2004_03/magazine/features/clarman/default.aspx
Indeed, there are some who have learned the notation or a UML tool, yet can't skillfully cut code in Java or design with patterns, and in some odd value system are therefore assigned a senior role as an analyst or architect who does the "advanced" work of drawing UML diagrams for others to program. Of course, the diagrams are worthless. Useful UML is sketched by deeply experienced OO programmers (ideally in pairs at whiteboards) as an aid to creative thought and communication before they themselves use their own sketches as inspiration during programming.
Мой препод, который работает в IBM системным аналитиком, считает, что UML - это просто удобство. В частности для него это удобство to communicate his ideas тем, с кем он ведет споры и дискуссии об модели. Как бы возможность говорить на одном языке, устраняет несогласия из-за разного толкования одного и того же.
Сабина