Terrible case of thread hijack this, but anyway.
What about 4.) Add thrust.
Just very quickly, without thinking about it to much
, I think part of the reasoning is in the fact we have a high sink rate - perhaps because we've let the speed wash off to below Vref. We're now well on the back of the drag curve, so pulling back simply increases the drag and we slam it in.
Also, I know from experience that if you pull back at just the wrong moment you do rotate the gear harder onto the runway. It may be a small moment, but it certainly has an effect.
And thirdly, as I mentioned before, there just isn't enough time with a high sink rate and a late pull for the aircraft to change it's vector into the tarmac.
Proof of this is also seen in the case where you have a high sink rate but a margin of speed over Vref. In this case the landing can be saved with a pull (as long as it's not too late) as the lift increases rapidly with increase in AOA due to the excess speed. The ground cushion is also more effective in this case - think of the float one gets with a flapless landing.
All the above applies to certain jet transport types, not to light aircraft with so much less inertia.
Sorry there's no equations - not my strong point!
