It is possible to corner weight the car and keep the ride heights equal. It just takes time playing with it - at least when I did mine. Numerous iterations, I had perfect 50/50 and the heights were off. But, I eventually got 50.0/50.0 and corner ride heights within 1/8". I had half a tank of gas and 200 pounds of bricks in my driver's seat when I did it.

When I was racing go karts, we had to come in at a minimum weight and the skinny racers bolted on lead. When we worked on the karts, we'd lift them up onto a stand. The etiquette is you would just ask someone that was walking by to help lift the kart onto the stand. Everyone would avoid skinny Rob because he had 60 pounds of lead on his seat.

I had a 1999 BMW M Raodster. BMW proudly advertised it's 50/50 weight distribution. Those cars have 40 pounds of lead in the rear bumper.