Quote Originally Posted by Seraphor View Post
As opposed to a 30m duration it currently is?

No, because they're mutually exclusive, you can only mitigate half of all damage, on average.
Protect doesn't reduce Physical and Magical damage received 10%. It increases Defense and Magic Defense by 15% which equates to like ~3% reduction. You are asking for free mitigation that lasts 5 minutes with a 10 second cooldown. Everyone would literally just keep Protect up until Shell is needed for AoE/Tank Buster and than instantly change back to Protect. It fixes nothing and just grants more mitigation for free.

Why would it last 5 minutes and only have a 10 second CD? It would function the same if the CD didn't even exist.