How do The Coming Calamity + Mastermind of Discord interact?

So, The Coming Calamity says "Mana reservation of Herald skills is always 45%" while Mastermind of Discord (Elementalist node) decreases the cost of Herald skills by 25%.

Will the cost reduction get ignored, or will it apply to reduce the 45% cost by 25%?

If something says that something will always be something, it will always be something.