I like the idea of really simplifying the rules elements (i.e. providing DMs with the framework they need with which to make consistent rulings) rather than just having everything spelled out. Of course, I am also primarily a DM. At least one of my players would throw a fit if this were done. He doesn't do it to be a problem, or even consciously I think, but he's the type who will always, every time, read every single rule, power, feat, etc. in such a way as to make it most favorable to him. For him, its definitely much better to have things spelled out plainly in the rules rather than merely setting up guidelines for the DM. If I can say "No, that doesn't work, look at page 247." he's fine with it. If I say "No, that's now how I'd rule it" though he'll not be satisfied.
In the end, its just another one of those cases of different strokes for different folks. For the hobby as a whole, I'm not sure which is better. Simplified rules make for a nice entry way for new players as its not nearly as daunting to look at the piles of books containing rules, but a system like this might also be a bit more intimidating to DMs. As it stands now, if I know there's a decent chance the party will go swimming in the next session, I can look up those rules ahead of time to refresh my memory and then be good to go (same applies to any situation really).