The assumption which you seem to be working under is that a resource-management system must, in order to be effective and fun, include attrition over the course of a day.
I disagree. From my experience with other games, this is simply not the case. I've had enormous fun playing and running
Mutants & Masterminds and
Iron Heroes, and both systems minimize the per-day resource management ideal and the concept of attrition.
What the system we are currently speculating about seems to imply is that the basic unit of measurement for resource management is shifting from the macro-management of the "day" to the micro-management of the "round". Under this model, the question isn't, "Do I use my fireball now or save it for another fight?" Instead, it's, "Do I throw my fireball this round and take out the goblins or do I hit the BBEG with a lightning bolt?" The fundamental resource in the game becomes the actions you have available to you (which IH did a wonderful job with using its tokens system... you could spend actions to get tokes, which you could spend in later rounds to activate abilities).
From what you describe, you tend to see encounters as "speed-bumps". You need to put X number of encounters in the way of the heroes in a given adenture not because the adventure calls for those fights in particular, but because the PCs need to suffer the attrition that those encounters will impose for the adventure to function correctly. You might have planned a heroic battle over a chasm on a swaying rope bridge and maybe a terrific encounter where the heroes encounter their first terrifying medusa before they square off with the dragon, but you then decide you need to go back and insert another encounter before the dragon lest that fight be too easy.
The upside to this viewpoint is that it promotes a very tactical sort of resource management. After each battle, the heroes need to take stock of what they have left and decide if they can go on or if they need to rest and heal. If you enjoy this sort of thing, then the system works wonderfully for that. I would still say it has difficulties in handling different degrees of resource management specifically because it's built around the 4-encounter per day system, but in the scheme of things, this is a minor point.
The downside is that you are sometimes forced to introduce challenges that are there
only to cost resources, as both yourself and RC have described. Certainly this isn't the majority of encounters, but they're a sort of "necessary evil" for you to get the PCs where you want them before the next encounter. I know this from personal experience. While designing adventures, I sometimes find myself adding an extra fight as an afterthought if only to make the final fight that much more of a challenging. They serve no other purpose than to chew up resources.
And I don't find that to be good design. RC talks about what makes an encounter important in terms of what resources it costs. I think about encounters as important in terms of how they move the game forward. If attrition as a
de facto requirement is reduced or removed from the game, then that's one less thing for me to worry about when designing an adventure. I'd rather make every encounter one that's exciting and moves the game forward as opposed to having to throw speed-bumps at the PCs to make sure that they're just the right sort of tired when they reach the end of the adventure.
Long-term resource management is one approach. So is short-term round-based resource management. I find that the latter better promotes the sort of games I want to play and run because they are less-likely to enforce artificial, rules-based restrictions on pacing. I also feel that the latter is superior because it allows for different types of pacing, but would join with you in agreeing that the per-day model does better allow for long-term resource management better than this model.
But personally, I value good pacing and meaningful, exciting encounters over long-term resource management. I like an RPG to run more like an adventure than a detatched, tactical game. This is a personal preference and nothing more, but I am pleased to see that this is one which WotC is recognizing as a valid one alongside their "classic" model of long-term resource management.
And by the way, even under a per-encounter model, it's still not too difficult to add attrition. Fatigue rules are a wonderful thing
