The card says reduces the cost of playing the ally. Which most of our players take to mean the IP gets 2 less threat when rebels play an ally.
The IP has pointed out the books says gains threat on card and Allied operations does not say reduce the "card" it says reduce the cost.
the question is what cost is being reduced? It does seem clear the only cost is threat cost, but this game is difficult for everyone and rules errors can cause a win or loss which we don't want to be the reason anyone is losing.