Feel free to correct my mistakes.
For those of you wondering what a drop-doo-hickie is, it's using a section from 1 pair of spindles to lengthen another below the spindle. The object is to have your lower control arm slightly angled downwards (just about like they are from the factory, although strangely enogh, my car had horizontal A-arms and I don't think it was ever lowered) so that when the car is cornering hard, the A-arm goes horizontal. As the A-arm swings horizontal, the base of the rim gets pushed outwards...which gives you negative camber. This in conjuction with the upper control arm swinging more towards vertical will give a considerable amount of negative camber on a fully loaded front end.
What I've gone and done with my suspension, is lowered the car so low that both my LCA (lower control arm) and my upper control arm are already in the upwards direction. When I compress my suspension by going around a turn hard, the LCA become even more vertical...which pulls the rim inwards, resulting in less negative camber, or positive camber.
So, what's the point of giving your car negative camber at stock ride-height if it's going to be replaced with positive camber when you're cornering and actually need it? The entire point of the negative camber is to keep the tire tread flat on the pavement as the tire is pulled away away from the rim as you screech around a turn to maximize lateral or side to side traction.
Now, you could just pile on TONS of negative camber (like -4 or -5 degrees!) to maintain some negative camber with a knackered front end like mine, but then only part of your tread would be touching the ground, greatly reducing your traction in the foward and back direction (read: braking). With drop spindles, apparently you can run as little as -1.5 degrees of negative camber, but once you load up your suspension, it could increase rather than become positive...a win-win situation basically.
The other way to get around having a decreasing camber curve would be to make your spring rates ultra stiff! You won't gain much positive camber if your LCA's barely move after all. I belive this would be the approach of the RSR system. It seems to work great so it can't be disregarded (not to mention the look and quality of the system is said to be top notch!) but I think it's more suited for smooth tracks than our rough CA roads. Greg Gordon has recently installed this system on SuperRedVerde with stock torsion bars, and he says the ride is even better than with 27.3mm T-bars, so I might be wrong here.
First pic is of my car, slammed with my suspension mods in the sig. That's as the vehicle rests, with -1 degree of camber.
Second pic is what my camber might look like when I'm cornering hard (my negative camber turns into positive camber, decreasing my front end grip drastically). The end result is a car that seems to want to terminally understeer unless I make the rear end ridiculously stiff.
Third pic is my idea of what a drop spindle will do to the front end geometry. You can see that the lower control arm is slightly angled downwards (yet the car should still be low...something you can't do with the stock geometry). This is better for bump steer also..something I'mnot going to get into because I don't think I understand it yet.
Fourth pic is what I think the suspension will do when thrown around a corner. The LCA goes horizontal, pushing the rim out (which adds more negative camber...usually good when cornering) and even keeps the steering arms at an acceptable angle (I think this is a good thing?).
