How much does overlapping the four spheres of Dancing Darkness reduce the light level?

Question

I see some ambiguity with the spell Dancing Darkness. What is the consensus on the following?

I take the usage of each in this rule to mean that the light reduction comes from all four orbs.

You create either up to four spheres of darkness that each reduce the illumination level by one step within a 20-foot-radius

This would mean that in an area on which all four radii overlap the light level would be reduced 4 levels.

The restriction on the relative position of each sphere may make this overlapping difficult to control, which I feel was intended because of this stacking of the orbs. With fine light level control coming from the fact that is up to four spheres. You could choose how many to change the light level from −1 to −4.

Answer 1

For a pretext, I'd like to list the light levels used in Pathfinder:

• Bright Light
• Normal Light
• Dim Light
• Darkness
• Deeper Darkness

On Deeper Darkness, it cannot be reached unless an effect specifically calls for it. So for spells that don't, reducing the light by 4 levels would take you from any light to Darkness.

However, that doesn't answer this question.

Dancing Darkness is actually not that powerful, being a first level spell

Light (and Darkness) spell are weighted against ambient light first, then each other if they coexist. From the FAQ for Light and Darkness effects:

Darkness spells first negate nonmagical light sources like lanterns and sunrods, and then they tell you how many steps to reduce the "ambient" light

Emphasis mine. What this means is that each orb of Dancing Darkness is weighed against ambient light, not each others' already reduced light. You could create a square-is shape 30x30ft of 1 less level, or a 20x50 length of -1 light level, but the central pieces would be just as dark as the edges.