Seems to be the case, which brings to mind the question, what is the point in breathing? 100% resistance to Asphyx damage doesn't help all that much unless you're precognitive.

1) Terror Covens (used to be 100% resistance to terror covens with no message to the coven that they were doing 0 damage, now it's just 50%)
2) Any skill which has an initiation and a time-to-finish, so you can trigger the starting line and have a timer tell you to start holding breath when it is near to firing. Essentially, the Aquamancer demesne effect.

Through the liberal application of hold breath, you can negate drowning damage while travelling/hunting underwater/swimming without a waterbreathe enchantment.