I recently created a new proposal on Area 51 for an Stack Exchange site called Design Review, which is meant to be an equivelent of SE's Code Review site. I put a lot of thought into the range of questions that could be asked on the site. A lot of it would not necessary be limited to graphic design, but all design, which would include somebody's final rendering of a 3D design, their layout of formal letters or resumes, and even a question such as 'how to make a night-time scene dark but visible in a drawing' or 'how to make my artwork look more scary/fast/quiet/1980s'. In a sense I think I conveyed my proposal as a Q&A site on Visual Communication.
Then I had a bit more thought about what the Graphic Design site is about and perhaps when this site was initially conceived, the intent was to be like my proposal. Also, such critique questions are generally valid here, as has been discussed before.
However, with so many questions regarding the software used to make these designs, which I believe do have their place on this site, it is easy to forget that questions regarding the design process are okay. Which is why I use the word fundamental in my question title. Also with most users like myself coming from Stack Overflow and that design is a fairly subjective topic, that having a technical question may seem like a requirement.