That is true but as an alternativ he could the trinket from ramstein.
https://vanilla-twinhead.twinstar.cz/?item=13515
Half the dmg from aq trinket but still not bad with enough spelldmg.
Additionaly the trinket from strath quest or gnomish deathray.
https://vanilla-twinhead.twinstar.cz/?item=13171
Ramstein is a 200 dmg hit in a 10 yard radius, which is not very compatible with Holy Shock's range. In Battlegrounds, you would break all CCs.
The trinket from strath quest being Smokey's Lighter requires you to stand still and channel. Don't forget to ask that enemy nicely to stand in front of you for 10 seconds.
Deathray is also channeled and will be interrupted.
Shard of the Fallen Star was used due to the fact that it is instant AND 30 yard range. Also the effect of having a meteor fall on your head (which was never before seen by people playing wow). And the fact that it deals highest damage of these options.
What you're missing is the fact that having a trinket dealing damage is beside the point. Your main trinket to deal damage is ZHC. The build is about burst damage coming from judgement and autocrit shock combo, empowered by amassing spell damage.
We should call it Trinkedin in vanilla
You are actually correct, because without the trinket, you're missing the crucial burst component. And if you really want to make it burst, get a load of goblin sapper charges. Ideal setup is Stun -> Judge -> Favor -> Shock -> Sapper Charge -> maxrank Consecration -> Reseal.
Like I said the idea of Shockadin is that u'r still a completely viable healer.
You should watch carefully the fight vs. Warrior in ungoro. That will tell you how viable healer you will be after a single fight. And again, there is no Shockadin on Vanilla.
This is a Shockadin
https://www.youtube.com/watch?v=a-GvjWTBv_w