Finding transfer function of Fender Stratocaster tone circuit

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The circuit of interest is the basic circuit for a Fender Stratocaster guitar. A diagram can be found at http://www.seymourduncan.com/support/schematics/S_1singlecoil_1vol_1tone.html . Basically an electric guitar works by vibrating a metal string in a magnetic field. This in turn causes a current to be generated in the an inductor that is wrapped around the magnet.

What I'm trying to do is find the frequency response of this circuit. Whenever I try to calculate the transfer function for this circuit I get

[tex]TF = 1[/tex].

When I try to calculate the total impedance for this circuit I get

[tex]Z_{total} = \frac{Z_{1}Z_{2}}{Z_{1}+Z_{2}} = \frac{(R_{1} - j\frac{1}{\omega C})R_{2}}{R_{1}-j \frac{1}{\omega C}+R_{2}}[/tex]

where
[tex]Z_{1} = R_{1} - j \omega C[/tex] and [tex]Z_{2} = R_{2}[/tex].

To find the transfer function I calculate

[tex]TF = \frac{V_{in}}{V_{out}} = 1[/tex].

This is obviously incorrect, but I don't know where my mistake is. Is my diagram correct?
 
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My post is a litle confusing. I had an ACII diagram, but it did not get rendered the way I wnated it to. R2 is the volume pot, and R1 is the tone pot.