It seems that in other books the main characters ( barring got) are protected by plot shield. Here's and example, halfway through the novel in a minor battle you know there's little to no chance of the main characters being injured, let alone killed. This is called plot shield in my mind, that the character is too important to the plot that they must live. Generally, shard plate/surges mean you're practically invincible in a fight. There's rare occursnxes in the book where shard bearers are killed, and no radiant has been killed yet. I'd say giving a character shards/surges means they are in the little bubble of invincibility unless the plot requires their death, and there's usually buildup to the death, so you know there will be no random out of the blue deaths of main characters