Technically they are both programmed to exist in the code at the same time and are therefore different objects within the code [like, running < Cacaphony == Soundproof > or < Soundproof.equals(Cacophony); > would both return false, or undefined/error if _.equals isn’t implemented]. :P
If we decide to care about this at all we could put on Soundproof’s page that there was once an unused ability called Cacophony that works exactly the same as Spundproof. :P