The definition of bump steer may be confusing to some. I had a 2002 ram that was lowered 5 inches in the front and 7 in the rear. The lower control arms sat real close to the bumpstops. In a turn, the outside wheel would hit bumps and make the truck skip. This made the steering wheel turn in more. It made the truck feel twitchy. To some, this SOUNDS like bump steer. It was actually a matter of the suspension running out of travel and the tire probably coming OFF of the pavement momentarily!
Actual bump steer is best described by one of the more experienced and skilled members here.