The old Hidden Voices system has a host of bugs which is why it's being phased out in favour of the new system that you can see when you talking to Chloe in Act Three :) Eventually all the characters will be using the new system.
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So does that mean it's going to become something more akin to a passive buff that you just won't have to bother using? I guess that could work but it would require some retconning unless you were to say that the MC has used it enough that it changed into a passive ability. Anyway, thanks for your time responding to me. :)