Banshee's Veil: Tooltip needs Clarification

Damage over Time abilities do not break the shield, I may or may not have stepped too far in trying to break multiple shields on the enemy team as Swain within the last week or so. Also, I'm wondering why Damage over Time abilities can't break Banshee's Veil.. Feels really bad as certain champions if they stack it against you, even if it's unintentionally...