S4,
Thank you.
I find that GMs from other games, used to modding them, come to CT with experience in d20, 3d6, or percentile games thinking that CT, with its 2d6 "decision space", as you put it, is the same beast that they've been used to. As you point out, it isn't.
I'm sure I cribbed the term "decision space" from somewhere, but I can't quite put my finger on it.
A long time ago, back when dinosaurs roamed the Earth and I was still working on a master's degree
by mail, I wrote a paper linking mathematical game theory with practical game design. All the stuff I wrote about 2D6, die roll modifiers, and "decision space" came from that.
Here's another little factoid to mull over; did you know that, from a mathematical standpoint, a wargame's odds-differentiated combat results table and a RPG's difficulty-differentiated task system are the
same thing?
Wargames generally operate within an even smaller decision space than most RPGs;
1D6, instead of 2D6, d20, etc. Yet wargames expand the potential outcomes of that tiny decision space through the use of odds or force ratios. By separating all possible, legal attacks into different odds/ratio columns, the 1D6 decision space is "cloned" or "expanded" to provide more potential outcomes. The die roll of two, for example, will have possibly different results depending on the odds: failure in a 1:2 attack, stalemate in a 1:1 attack, success in a 2:1 attack, and so on.
Equally importantly, this expansion also allows the combat results table to use more die roll and other modifiers. Because the decision space has been expanded, modifiers can now be more easily used to effect the combat factors involved, effect the die roll, effect the column being chosen, or any mixture of the three.
A difficulty-differentiated task system does the same thing to an RPG's decision space. By assigning different difficulty ratings to different RPG skill rolls, we are doing the same thing mathematically that we do when assigning different odds/force ratios to different wargame combat result table rolls. And, just as with expanding a wargame's decision space, expanding a RPG's decision space allows for more die roll modifiers.
After all, die roll modifiers appeal to a very human characteristic; the need for control or even the illusion of control. Adding die roll modifiers to a game, if not taken to extremes, can make a game more enjoyable.
This is what I tried to say in my original reply to the OP, but you said it so much better than I did.
That same thing happens to me all the time. I'll bloviate for several paragraphs on some point only to read some smarter fellow make the same point far more cogently with a sentence or two. Occasionally I can come up with the pithy phrase, but more often I end up "borrowing" it from some other, smarter guy.
Regards,
Bill