After all, in the absence of the CS mechanics, that hit would do max damage. Did the fighter suddenly, magically gain DR? After all, DR is a magical ability in 3e. Why isn't this a problem?
DR is not a magical ability. Barbarians get DR. Adamantine armor grants DR. In Trailblazer, any character with a couple of points of BAB can block similarly to this ability, except that they have to declare it before damage is calculated.
Note, the damage is rolled BEFORE CS dice, not after.
Note my post above, which I'll reiterate.
The player knows EXACTLY how much damage he's going to take before declaring that he will use a CS die.
That is not entirely clear from the very minimal rules text I see (which I believe forum rules prohibit me from copying).
Regardless, as I posted above, being able to declare this or any reaction after the action has been resolved is a retcon; one that I didn't notice earlier and assumed was not there. I would place that on the level of 3.0 Whirlwind Attack: if some fighter said they were dropping a bag of rats, I'd say no. Same with declaring a reaction too late. Why the rule is written this way is beyond me, but you have indeed pointed out that there was something in it I missed.
I would never even consider allowing parry to work as written. I bet I'm not the only one that read right over that (especially those of us that like Trailblazer and intuitively thought this worked the same way as TB does, see below).
I am now using my ability to non-retroactively change my mind about this specific playtest rule example, now that I see the problem.
Trailblazer said:
Block
If you are engaged in melee, you may use your combat reaction to block your
opponent’s melee attack. On the opponent’s turn, before he makes his attack
roll against you, announce your intention to use your combat reaction to Block.
Against that single attack, you gain DR against that attack equal to ½ your
BAB. If you are blocking with a buckler or shield, add the shield’s AC bonus
(including any enhancement bonus) to the amount of DR. If you have DR from
another source, the DR from block stacks with your highest applicable DR.
I think what this example illustrates, more than anything else, is people's willingness to ignore dissociation is directly related to whether or not they like the mechanic. IOW, dissociated claims are nothing more than claims of preference and not an actual reflection of the mechanics themselves.
Who's ignoring it? (See bolded text above).
Also, all this stuff above is really missing the point. You example is about one CS ability, not about CS. The relevant comparison is this:
Is giving a fighter X amount of dice to spend each round on various combat tricks as dissociative as giving the fighter one trick that can be used perfectly once and then cannot be used for another day and another completely separate trick with an unrelated recharge time? The answer to that question is no.
This specific CS maneuver example is pretty sketchy, but talking about that is like talking about one spell (say, polymorph), and then concluding that wizards are unbalanced. Similarly, there is a 3.5 feat (Goad), that forces opponents to attack you. This doesn't mean that feats break immersion because they grant mind control, it means that one specific feat does. Conversely, there are probably some examples of relatively non-dissociative fighter powers, but the power system itself is hopelessly disconnected from the game reality. The CS mechanic itself is fine (except that we haven't seen it applied to other martial classes yet), the parry maneuver needs a fix (as do several of them).
Hussar said:
I'm honestly not sure I could write a more dissociated mechanic than CS.
What if you said a character gained d6's, d8's, and d10's, the d6's refreshed each round, the d8's refreshed after the DM said the battle was over and you rested a bit, and the d10's refreshed after a whole night of rest. Then let's say you could spend a d10 to force an enemy to attack you instead of the defenseless wizard. That would be more dissociated.
*(Note to 5e designers: please do not copy this purposefully stupid example).