Wolfshirt clipping

[Lubdar]

I just wanted to clarify my understanding of the Wolfshirt's signal clipping.
It looks like the signal is clipped via diodes to ground before it hits the tonestack, but the way I've seen the diodes presented in schematics is usually attached to one of the legs of the bridged-t (low pass filter leg). 
My question is: Were the diodes in the FTM supposed to clip the signal pre-filter, or was the filter supposed to be clipping the waveform such as in http://www.muzique.com/lab/tclip.htm ?