This issue with comparisons based on knob position come up pretty regularly, so let me comment directly to this point.
One of the goals of the Subway project was to make it FEEL like a pro amp, that means that the controls operate over their entire range, smoothly and evenly. While this comes more from the pro audio perspective where feel and predictability of an adjustment is important over the entire range, this is not at all universal among bass and guitar amps. In fact, for the very reasons mentioned, having a control that appears more "active" earlier in the rotation gives the "impression" that an amp may be "louder" or "more powerful", when it is not. This, along with a specific voicing can leave the inaccurate impression if the player doesn't understand why it is this way and that it's intentional.
The Carbine is more traditional in that the controls are more active earlier in their rotation, which may explain the side by side comparison results, though the Subway will continue to get louder as you turn it up. I don't understand why folks would think that having a control with 270 degrees of rotation with only 120 degrees of adjustment is a benefit, but it continues to be done this way on some products.