Saving Throws, Critical Saving Throws, Class-Specific Saving Throws (really, for any D&D)

I left saving throws off my class rundown, because I struggle with them. Some days I think they're flabby, on other days, I like the granularity multiple saves afford. Here is the cleanest iteration I've been able to come up with. Admittedly, this is far from original. I've used a similar version in the past but it was clunkier, and +Mike Mearls's recent post about saves in Next brought me back to this concept. It's seen a single session of play, in this form, at this point.

SAVING THROWS

Are a mechanic that assist in determining your fate when you face a catastrophe.

CATASTROPHES

are things like:

• Character death
• poisons and toxins
• getting hit with an undesired spell or magical affect
• massive area of affect attacks
• catastrophic damage (hit with a giant stone, falling ceiling, stepped on by a massive monster)

SINGLE SCORE

Roll d20 + your level, aim for 19+.

CLASSES MATTER, CRITICAL SAVES

A Character's class indicates a certain extra facility or luck when facing down certain types of affects or when facing down catastrophes in a specific way and may also grant a critical save (roll a natural 19 or 20; or not). Players must declare their intention to use their character's class to augment their saving throw before rolling. 

Fighters can try to "withstand" catastrophe. Whenever a fighter grits her teeth and bears the brunt of an incoming assault, add two to the roll to save. Describe how you intend to do this. To critically save  you must be in a position to prevent others from taking damage; so long as you can convincingly repel the oncoming source of damage, you can prevent if from affecting others.

Rogues can try to avoid the attack entirely. Describe how you intend to do this and add two to the roll. To critically save you take way less, maybe no damage at all. 

Magic-Users can try to withstand spells or magical affects that can be cast by a Magic-User (add two to your save). When you critically save you can counter-spell and thereby unravel and the spell entirely.

Clerics can try to withstand spells or magical affects that can be cast by Clerics or Magic-Users (add two to your save). When you critically save you can counter-spell and thereby banish and negate the spell entirely. 

WHAT HAPPENS DIEGETICALLY ("IN THE FICTION")

When you fail:

you take the full affect, likely death, GM describes, likely gives you a last word or gesture

When you succeed:

if you're just rolling without  using your class, then the GM decides how what your character has done to minimize or avoid the catastrophe; or

if you're rolling using your class, the GM will decide how the save unfolds, based on how you've described your character using their class to augment the save.