When to use crafting brand skills?

[jjolin01]

So I got brand of ice, which has efficiency of 100% , which doubles if the craft has affinity to ice.

Now I was crafting ingots, which use ice shards, and it by no means was efficiency of 200%, it was the base 100%. My standard synthesis gives more progress.

So my question is, when am I suppose to use this to get the 200% efficiency?

[Scarletyoshi]

When the time is right, you'll know. You're synth will look like Shiva took a dump on it.

[SpinwardBound]

You'll use this when you're making something with your craft elemental affinity using recipes that require the worn gear looted from dungeons as a component. If you look in your log book at one of the recipes requiring the special component it will show it has an elemental affinity. Also, like scarletyoshi said, your crafting bench will light up.

If you use normal synthesis skills it won't advance your progress very far.