Very good ShawnQ - very straight forward.

I will take it a step further.

If I were open the hood on my pickup, I could hold the (mechanical) throttle linkage in my hand and pull back to make the engine go vrooom.

If I wanted a sprint booster for my truck, I would build a mechanical gear at a linkage point, say 2:1 ratio so that when I press my gas pedal down, at 1/4 pedal I would be at 1/2 throttle thus fooling me into thinking I had more performance (i just touch the pedal and man my trucks a rocket). But once I got to 1/2 pedal, I would be out of throttle response and the gig would be up and potential customers would gawk at such a silly device.

So I go back and design a lobe on my gear so I only get a 2:1 ratio on the first 3/8 of pedal travel and then back to something like 1:1 for the rest of the pedal travel. Ensuring the driver gets some throttle response when pressing the pedal to the floor.

That is all the sprint booster is. A simple amplifier (about $10 in parts - the connectors being the most expensive components) technology that's been around since the 1940's that adjusts the sensitivity of the pedal signal to the throttle controller. Not to much different then what's in you car stereo.

What I find amazing, is that people will lay down $280 for a $10 gizmo and then complain about the price of synthetic oil or tires etc...