This is a really good question, and in my opinion, yes. When you show someone your sketches, brainstorms, in-progress artworks, and rough drafts, you give them an insight into your thought process, how you work, how you solve problems, how flexible you are, and how much effort goes into making your finished masterpieces. This is valuable information for all kinds of situations. I would say, show one or two completed works along with your sketches, rough drafts that relate to those artworks, even if the artworks are not done.
You want to tell a story...this is how I come up with an idea, this is how I sketched it out, this is how I reacted to the ideas of my teachers and other students (critiques), this is how I changed something to improve it, this is how I reflect on what I have created.
For most of my teaching career, I worked in an IB School (International Baccalaureate), and to prepare students for future portfolio reviews in high school, we were to advise students that their sketchbooks and all the work behind the artwork were as important as the artwork itself.