[Toffee]

I'm playing a Destiny Rogue with main-class Engineer and subclass Spellthief. I also have a Dar'Ensha Plus equipped and have noticed that, while my Rogue skills receive the -10% FP cost, both of my skills for my promoted classes aren't discounted at all. Every engineer robot costs the same 50 FP in both the skill list, hotbar previews, and the FP bar itself (I triple-checked to make sure it wasn't just the skill previews). Spellthief skills also cost the same, meaning that my promoted classes aren't being discounted at all.

[Neus]

This has been corrected in 2.66b.

[Toffee]

Tested the Dar'Ensha Plus in 2.66b and it's still not working properly. Once again, I tested both the skill previews and the actual FP cost of the skills and there was no discount for promoted classes.

Below are my FP bar before and after using an engineer bot, showing the same 50 FP cost.

[Neus]

I can confirm this will be fixed in 2.67.