From what I can see, the only arbitrary part would be how the wing is sectioned.
Ok, lets say HT models the wing in two sections. Each section has lift, drag, etc. forces put in the FM for it. Now all that happens when you lose a "wing tip" is that outer section gets removed. The lift, drag, etc. from that bit gets removed also. Depending on how long that piece was, and how the wing was shaped, the plane will fly differently missing that bit. In some planes that outside section may be a greater percentage of the lift than in others, so some will still be able to fly, while others will not. I believe HTC just removes the section and the forces it generates from the FM, and let the chips fall where they may.
So I don't believe the effect is arbitrary at all. The only arbitrary part, (and HTC may very well have some means to determine this so it may not be arbitrary at all) may be where you draw the line between the sections. Once you do that and apply the different forces, when the outer section gets removed, so do the forces that went with it. Simple.
Now, I want to make it clear I don't REALLY know how this works. I'm taking a shot at how I think it MIGHT work here. The effects I see do seem to support my guess though.

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Sean "Lephturn" Conrad - Aces High Chief Trainer
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