I think it depends on the working environment. At Nike there are about 150 designers just designing product. Very traditional ID collaborating with engineering, advanced design, testing labs, marketing, research, all those things, but very focused on design. That is not going to change. At frog with have more of a cable type of approach. The directors are very broad thinking, but the entry level designers need a strong disciplinary based skill set. I wrote a small piece about it here:
http://www.core77.com/blog/news/buildin ... _17703.asp
other places have very few design resources, so those designers need to wear more hats, I think that is more like what you are talking about. There are no rights and wrongs, it all depends on what kinds of designer you want to be. I've always been a collaborator who likes do a lot of up front conceptualization and then bring the right people in along the way to build, test, validate. By doing this I can work on many different projects simultaneously, influencing the outcomes.... other people like to do it all and to tightly control the outcome, while only being able to do one or two projects at a time because of that desire. Both are valid techniques as long as the results are strong and you are having fun.
Back to the topic, it is difficult to construct a group for this diverse array of people. I'd like to see someone try though!