Probably old news to the pros, but for the new folks helping out on construction, listen.

Application bases ALL of your XP on CURRENT. And it reduces your XP down to 0 as you approach 200 skill above optimal. MOST crafting is based on 'base' skill. Making the blocks/bolts/timbers/spheres is based on 'base' skill. Not application though.

So take off your jewelry and/or clothing and equip the appropriate tier tool before applying to make sure that you are at the LOWEST possible skill and still 2:1 (optimal).

For example, a load of Obsidian Keystones with jewelry (18 units), I get 1,200xp (hahaha). Without jewelry, I get 17,000 xp. etc... which kinda sucks when I forget to take it off, which I do regularly, but oh well.

-HratLi