I'd just like to reiterate that this worked on the PTR, so it's not a question of whether or not atonement is intended to benefit from the crit heal change.
On the PTR, atonement damage (smite/holyfire) would crit for 1.5, but the heal would crit for 2.0
PTR example:
*smite hits for 10,000 -> atonement heals for 10,000
*smite crits for 15,000 -> atonement heals for 20,000
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LIVE example:
*smite hits for 10,000 -> atonement heals for 10,000
*smite crits for 15,000 -> atonement heals for 15,000