Hey mate, I dont come here much these days..but yeh anyways to answer your question, if your going into engineering jobs, by doing a combined segree with anything (not just commerce) you will stand out more and will probably give you a better chnace in getting an interview...thats about it. It will not do much more than that.
I did it because of two reasons, 1. you get interviews much easier, but mainly 2. because you will know alot about the commercial/business side of things and this is really common sense but it does help you in an engineering job as well. I work for TransGrid now and from my rotation in "project management" I did more stuff related to commerce than what I did in engineering..so it does help you out having done some formal study in that area.
I did it because of two reasons, 1. you get interviews much easier, but mainly 2. because you will know alot about the commercial/business side of things and this is really common sense but it does help you in an engineering job as well. I work for TransGrid now and from my rotation in "project management" I did more stuff related to commerce than what I did in engineering..so it does help you out having done some formal study in that area.