Speed sensitive steering is no more likely to pull than other systems. Uptown SVXs have speed sensitive steering and they don't exhibit the problem. Actually you'd be surprised how many cars do have the feature.
Fighting road crowns has always been the bane of alignment techs. Catch 22, damned if you do, etc. Typically a tech would figure on a 1/2 degree caster difference pushing left to counterract a 1 1/2" crown. But that's with rear wheel drive. Figure in unequal shaft lengths and drivetrain drag on fwd cars and you just play it by ear. I used to work in an area of Denver where most everyone drove the interstates to work. Imagine trying to explain to some hardheads how the dually ruts from large trucks didn't match the track width of their Honda. The car would be 'swimming' in the ruts and there's absolutely no way to make the car drive straight without constant corrections. Sorry, buy a Peterbilt...
Quick primer on alignments: Three basic angles - camber, caster and toe. Camber is the tilt of the wheel in or out at the top - top of the wheel towards the car is negative and away from the car is positive. Camber pretty much stays constant in cars with strut suspension, and as such normally runs close to straight up or '0' degrees. Cars with unequal length 'A' arms have fairly dynamic camber, as the suspension moves up and down the camber changes quite a bit. Typically these cars will have 1/2 deg. positive camber. Think of camber in the terms of a Dixie cup on its side. It has two distinct diameters, and if pushed forward it will travel in a circle. If you force the cup straight ahead one diameter spins faster than the other. If a wheel has excessive camber the diameter differential comes into play and you can bet the tire will be ripped to shreds. Camber has little effect on pulling unless, obvously, it is so far from spec as to cause drag from the uneven tread diameters.
Caster is like the front wheel on a bicycle. Notice how the fork at the wheel is farther ahead than the handlebars? That's positive caster. On a car the wheel with the most positive caster will push harder towards the center of the car. More positive caster will also give more 'returnability' (steering wheel returning to center after a turn) and stability to the steering - to a point. Excessively positive caster can cause violent shaking in some vehicles. Older Chevy rwd pick-ups were notorious for it - a lot of miles + a poor alignment + 45mph + a big pothole and it was off to the races. Hopefully you didn't have manual steering with your thumbs inside the steering wheel. The only way to stop the shaking was to stop the truck (which you had to do in order to change your laundry anyway.) It's not the only vehicle to do it, but it was probably the most common. You would never forget the experience, the fenders jumping up and down, the steering wheel constantly whipping back and forth 3/4 of a turn and the noise of the truck beating itself to death. Whew!
Well, to get back on track
toe or 'toe-in' is how the wheels sit, pigeon-toed or duck-footed. Toe is absolutely the most critical adjustment, the most easily knocked out of alignment and the biggest cause of tire wear, next to underinflation. Toe on most cars is critical to .125". For rwd cars the toe is usually set 'in', because as the car drives forward the tires will drag back and 'out', to a parallel position. With fwd cars the toe is usually 'out' and the wheels pull 'in' as a result of power application. However that's not a hard and fast rule anymore, different geometry, bushings, etc. will cause some fwd cars to be set 'in' also. Basically the thing to watch for is tire wear on the inside or outside of the tires. If the wear is equally placed on both tires it's more than likely toe, if only on one tire or inside of one, outside of the other it's probably camber. Incorrect toe will cause wear on the leading edge of the tires - excessive toe-out will wear the inside edge of the tires and vice-versa.
There's a lot of other considerations, but those are the basics. Sorry for the looong post, but I needed something to do while waiting for sleep mode to kick in...
Beav