Matt McLane's page

So the Phylactery of Positive Channeling says:

This item allows channelers of positive energy to increase .....

Cure Light Wounds states:

When laying your hand upon a living creature, you channel positive energy that ...

Or Cure Light Wounds, Mass:

You channel positive energy to...

So in my mind when you cast a cure spell you are channeling positive energy and therefore your phylactery of positive channeling should do its thing.

I have been told however that the Phylactery of Positive Channeling only enhances the effects of the Channel Energy super natural ability of the cleric and NOTHING else.

So my question is, what is it? Where does it state that the phylactery of positive channeling is limited in this way? Why doesn't this item increase Cure spells?