I don't know what you read, but that is not what he said at all. This is what he said in regards to potentially changing the way bosses do damage and the way that damage is avoided/mitigated:
"Not all channels of survivability can be balanced for every boss encounter, which is why tank survivability is measured against a norm, and why we're going to be pushing harder to hit that norm in the future - either through tweaks in boss damage or tweaks to the way shields work."
He clearly said it is a known problem that they are going to be working on.
You know "tweaks" is code for "nerfs", right?