Because Golden Lace has the Evade-Skill. She is my Dodge Tank
http://flowerknight.wikia.com/wiki/Golden_Lace
If i decide to give the other girls the taunt skill as well her Tank Role would be redundant (the 16 % less Damage for the other girls would be n1 though).
Spending 600 Life Crystals is really expensive however.
My idea was to hoard Rainbow Skill Blooms for my Crit Team so the enormous cost of 600 Life Crystals for another Promotion ability kinda sucks