JEL said:
I don't like it for the same reason I didn't like how Perform used to be handled. It just doesn't make sense and it completely waters down character concepts (unless your concept was some sort of super genius who knows everything).
Well, then perhaps you aren't giving it a chance because of perform. There are big differences between performance and knowledge in terms of education. A performer picks up new skills laterally. That is, if I'm an actor as I act it's also probably going to be pretty easy for me to pick up skill in fashion, cosmetics, and various aspects of stage design or direction, not to mention dancing, acrobatics, stage combat, singing, and so forth. Certainly that's true if I'm a talented one. But most of these things I'm going to pick up because it's convenient or helpful.
Education, on the other hand, begets education. A historian is going to be close to as expert in politics, philosophy, and popular culture and is only going to get more so. Probably going to pick up a fair amount of science, environmentalism, religion, economics, and military science as well. As he gets better at history he's going to pick up more from other fields and because he's so good at the one knowledge he's never going to be a neophyte in the others and the time it takes him to catch up is going to be very truncated.
Now I'm not saying that someone who publishes in history is necessarilly going to publish in physics, though it does happen more frequently than you might think history of science is pretty interesting field and there are certainly physicists who do historical work as well, but I'd argue that publication fits under profession: historian or physicist. The actual knowledge and the ability to access it, understand it, or explain it is always going to be broader than the field of scholars who can work in it.
It seems to me that a one knowledge skill model with a high level of granularity simulates that very well. You've got this one skill and that represents
your education. You determine what you've been educated in and what you're going to pick up. It seems to me that this works better than DnD because it doesn't make getting an education a cost prohibitive or structurally limited exercise. It seems to me that it also works better in terms of character concept because you get to determine what your specialties are.
A smaller list of broad specialities is an intriguing notion, but I'm not yet certain I understand how it competes. Particularly since in the one skill system I don't think you have to pick up more specialties if you don't want to and at least this way the guy who wants more granularity isn't crippled otherwise.
Could you explain more about the watering down of character concept?
And I have no clue where you're pulling "three knowledge areas" out of.
The 'a few broad based areas' from your original post. Three seemed like a decent number to assign to it, but if you have a more specific one in mind then please go with that. I was simply assuming far fewer than the current DnD system.