When you use any rank of either Cannon: Scatter Volley or Cannon: Rapid Fire, the base +10 Crit Severity buff on Dual Heavy Cannons is removed.
Tested on various DHC, all lost their +10 CrtD when buffed.
Buffed by Cannon: Rapid Fire
Buffed by Cannon: Scatter Volley
Credit goes to @Snipey47a
for noticing it with his CRF.
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