The 5,000 health bonus to pets don't apply when a duel is initiated. Additionally, player abilities do full damage to them. I had a friend hit my Clannfear in both a duel and in Cyrodiil using the same build, and the Clannfear was taking double the damage from the attack during the duel.
Edited by Alpheu5 on October 10, 2016 4:10AM Dalek-Rok - Argonian Sorcerer ||
Dalek-Shād - Argonian Nightblade ||
Dalek-Shul - Argonian Templar ||
Dalek-Xal - Argonian Dragonknight ||
Mounts-the-Snout - Argonian Warden ||
Dalek-Xul - Argonian Necromancer ||
Two-Spires - Argonian Arcanist ||
Dalek-Nesh - Argonian Sorcerer ||
Dalek-Kör - Argonian Dragonknight
Don't incorporate bugs into your builds, and you won't have [an] issue.