Elemental Weapon is supposed to apply a random status effect (Burning, Concussion, Chilled). Obviously, you'll never get a perfect 1/3 for all status effects, but over a big enough sample size, you should see the numbers gravitate towards 33%.
Adding up my most recent 4 parses:
Chilled (Minor Maim) - 60, 61, 76, 48 = 245
Concussion (Minor Vulnerability) - 29, 23, 24, 13 = 89
Burning - 56, 45, 58, 33 = 192
Elemental Weapon Casts - 145, 129, 158, 94 = 526
Final %'s
Chilled - 245/526(46.6%)
Concussion - 89/526(16.9%)
Burning - 192/526(36.5%)
Chilled is applying almost 3x more often than Concussion.
This was all done with only Elemental Drain and an Inferno Staff (no gear, enchants, etc).
Also tested to see if it depended on what type of staff you had on, but it did not.
Edited by LZH on April 28, 2018 3:01PM