sounds like a wash to me, unless I'm not understanding. I'd too like to see a pic of the mod. Maybe if your transition was too wet & sloppy, but the idle was too fuel-starved to sustain, such a mod could correct that imbalance by allowing you to lean the low speed needle without further starving the idle of fuel. I'm just speculating. But it especially makes sense if you have an accelerator pump like you said. The pump would richen the transition a lot.