I'll go the other way. Shatter spirit should be removed from the game, and obliterate limited to only being able to be cast as a full on ritual, never thrown or spellstruck as dragon magic.
The things that require these to make big fights scary are gone under .10. Ensure Res effects are going to do just that, because the defensive stacks are gone for everybody but formalists.
The 0.9 Corrupt, I think, has the right level of danger and you have 5 minutes to save take'em down and life'em, but instead of lying on the ground dead, the player is engaged in the encounter/fight/module still.
Talk to your plot team. This isn't something that needs to be limited by a national rule. I think it's fine that it's a tool plot teams have but, it's one that should be uncommon for sure.
In general I think it's important to give plot teams a lot of tools. Running plot is hard work. No need to make it harder.
That being said it should be rare. In the past 7 years, I think we at South Michigan have thrown 3? 5? With only one taking effect. And 0 obliterates.
Traverse City has an even better record. I don't think I've seen a single shatter spirit or obliterate at any of their games in the past 4 years.
I tend to feel just the opposite. Card abilities that can utterly destroy a visiting character need to be something whose place in scaling is strongly considered at the national level, because they have effects that go well beyond the local chapter.
I like all of this except the 5 minutes. 5 minutes kind of encourages players to go in and die, even if it's subconscious. It can be not fun as you are forced to beat up your friends and also you're about to rez.
I think if this effect lasted 5 days and then maybe you're transformed fully into undead. That'd be a bit better. Since it lets players have a bit of fun, since it's a tad bit less risky.
To go this route isn't that hard with the existing 1.3 Infection/Curse of Transformation monster abilities. Even Adam's version could be done with these abilities. As long as you bring a bunch of stacker cards with important information on them, you can use these abilities on the field.