I have been trying to turn effects off by controlling the wet/dry or wet levels, but it doesn't seem to work. Here are some bindings that don't work...
<binding type="effect" level="instrument" position="4" parameter="FX_REVERB_WET_LEVEL" translation="fixed_value" translationValue="0.0" />
<binding type="ui" level="control" position="2" parameter="value" translation="fixed_value" translationValue="0.8" /> (to a control that binds to FX_REVERB_WET_LEVEL)