I'm trying to help.
I don't know how big of a gear head you are, so I'm going with a way "simplified" analogy here. Also the car analogy really doesn't work very well, so you have to group some things together for (i), but I think I can make it work.
BL= the motor strength of the car, max horsepower and torque only, throw away RPM.
M= the total weight of the vehicle
a= the 1/4 mile time. You will have to assume a perfect run every time.
i=would be anything that would affect power transfer to the ground, use gear ratio here In real life the engines power band (which is affected by a billion things) plays a critical role with gearing, so just assume that it's perfect for the gears selected. Also assume a perfect tire combo, and launch.
Race 1- mass is an issue when racing a stock 57 chevy with a trunk full of cement(high M), and a rail car (low M)with the same engine(BL) and gearing(i). Everyone sees that, no contest. The 57's extreme mass will slow it down.
Race 2- how about two 67 camero's only one has four people in it, and the gas topped off. Same BL, one has more M but not to much for the engine. This time its a lot closer, with the heavier car only a few tics behind.
Race 3- take two more which have the same BL and M and change the rear ends(i). One has 3.15(higher i) and the other has 4.10(lower i). This is an easy one again, the lower gear (the one with the higher number) pulls harder longer and pulls into the lead around the 1/8th and never lets up.
Race 4- now lets go back to Race 2 and give the good'ole boys a set of 5.10(lower i) and the solo the 3.15's(higher i). (remember to magically change the power band as well)This time solo makes it out of the hole faster but around mid track it's neck and neck, with the good'ole boys finishing a car length ahead of solo.
Good speakers generally fall into a Race 2 or 4 scenario. A good speaker with a heavy cone will have a large enough magnet to control it fairly well. If it doesn't it's a POS. A light cone with a crazy strong magnet will be induction limited. Still the more B in the BL the better just like a car, until your wallet cries anyway.
The best way to look at it is that if the BL and M are pretty close (i) will always be the deciding factor. If the mass is way off, then why are you considering it? It would be like your manhole cover and tweeter motor, dumb idea. It would have to be way off to even matter though. Looking at their example they added more than double the weight, and the change was very slight. Now when they changed the inductance there was a noticeable(on the graph) change.
|Now, taking the car example further...I would think that the shorter the distance you're racing, the more the "start" will matter. In the same way...I can see that when excursion is low...the inductance would seem to matter more, but once you start getting into higher excursions, it would seem that BL and mms would start to matter a lot more.|
The start matters, no matter the distance. For every wave there is a race to push the driver one way, an another to push it back the other. A rise and fall, positive and negative. Once the wave crests the polarity changes and the cone is pulled the other way by the motor to complete the wave. It doesn't just push it out and let it snap back home, it controls it both ways. Another thing is that BL isn't constant with excursion, but that is another can of worms all together.
Higher excursion comes with lower frequency waves, and higher SPLs. If inductance didn't matter at high excursion levels, all speakers would sound progressively different as the volume goes up.
EDIT: I'm assuming you understand the impulse graph. This is the non-techie version. Looking at the graph think of the horizontal 0 line as the cones home position. The graph shows how far it moved forward and backward on the vertical axis. The other shows time. You want the highest first peak in the shortest amount of time possible, and then it should stabilize after the second peak into a flat line ASAP. Notice the green one never quite got the tone completely out before heading back the other way. Lazy good for nothing.