Oh yeah, of course. This situation is exactly the one which makes me want that the shield effect should only be replaced if the new one provides more shield.
But whatever the case, I wouldn't want to run in Nocturnal with a SCH anyway (except maybe for very specific cases where my raid healer (SCH) would want me to... but as you said, that require raid awareness). I was just comparing Adlo and N.AB. Only at the very moment when the big green crit number is displayed on the screen. Otherwise, no. The buff icon isn't different and nothing else would tell you.
Even the SCH himself can completly miss that he did a crit Adlo if he didn't pay attention to his own number.
