This will just create a meta of "Who is the best Fervor user?" and will remove other picks from the meta. It's not even a choice anymore. If you want to get Warlord's, it's going to be a lot worse so champions for which both are good (Fervor and Warlord's both have 48% winrate for Tristana) will no longer even consider Warlord's. Meanwhile, champions for which only Warlord's is attractive will be gone from the meta.