Avid Pro Multiband Dynamics Plug-in - deapth versus ratio

[Gm167704]

Hi there,
I am interested in purchasing Avid's Pro Multiband Dynamics - I am trying to get a bit more clarity as to how the depth setting works and how i can clearly understand it's relationship to a more classic ratio control. i think i am just generally confused and could use some wisdom.

the manual states:

The Depth control sets the maximum amount of gain reduction or expansion applied to the input signal of the band (from –24 dB to +24 dB). For example, if you set Depth to –10 dB, no more than 10 dB of gain reduction is applied to the incoming signal. You can also adjust the Depth setting using the purple triangle Depth control on the FFT display.

So, if i understand this correctly then, depth simply sets a limit to how much compression or expansion can happen to a given signal right? So does that mean that the Pro multiband dynamic has a ratio in which it compresses and expands signals that is nonadjustable? and instead uses deapth as it functions in a generally similar way? perhaps due to it's also being an expander?

thanks guys