There is one thing though.
I have many duels that go like this. My opponent and I begin at 100% health. We bow, and fight honourably for a while. Eventually, I do some damage so my opponent is at say 70% health. At this point they WoG spam until my health drops to 70%. Then their talisman goes away and the shield comes back out.
This continues until my opponent wins, or I'm about to win and they spam WoG. This really gets my goat.
If you run into a fight and spam WoG someone to death, fine. It's a powerful spell feel free to use it. If you use it at opportune times to block backstabs and/or knock people off ledges, then good! That is its intended use!
Using it as an equaliser when you're losing though is a completely different matter. It's like admitting its overpowered and using it as your own personal handicap in a game that's supposed to be brutally fair.