Free lesson in game mechanics on that one. Not a lot of people know that. So for the gear swapping aforementioned the Won Khim Lao as an example will make your physical attacks and by proxy Tempest Rush deal Lightning damage. Which will be increased by the special ability of the Won Khim Lao which states Lightning Skills Deal x% more damage [not to be confused with Add % to Lightning Damage]
I am a bit skeptic about this. Any confirmation or testing done?