Okay here is is some clarification.
http://wiki.bluegartr.com/bg/Tatter_and_Scrap_Synergy
"You synergize your armor with the appropriate scrap or tatter (your synergy skill level and final elemental alignment influence the HQ tier of the result).
It is possible to determine the HQ tier of the result from the Cinder yield (see the table below)."
I know it's a wiki and all, so I don't take it at 100% truth unless someone can confirm.
From the wiki it sounds like alignment matters especially when trying to get the higher augments. Yes it is random but there are ways to give yourself a better chance, or so it would seem.
So I was wondering if anyone had any additional info than what is on the wiki, or can confirm/dispute what is posted there. Advice on how to balance the elements (where to start), whether impurity matters for HQ, etc. Specific to augmenting gear (not normal crafting).