My experience with LGB table layouts is that the trains tend to run flawlessly without a derailment. After enjoying straw 124's family story, with the excellent pictures, I duly noted that each of the layouts were essentially LGB "floor layouts".
LGB is great for floor layouts, and a layout can be set up in very little time -- unlike Lionel standard gauge, which may require some significant track "mating rituals". (In this regard, Art has a proven technique for assembling standard gauge track.)
Of course, having proven on many occasions that gravity works, I did make a mistake one day in leaving my LGB trains running to go retrieve something upstairs. As it turns out, my second mistake was relying solely on the proven tracking prowess of the LGB trains, and, not installing a side rail on my LGB layout to protect the trains in the event of a derailment.
Upon my return to the basement, I found that my largest German made LGB engine had derailed, and had crashed to the floor. Upon examination, the pilot and front end of the locomotive was damaged. Since I liked the look of the layout without sides, I decided that in the future I would stay near the layout while the LGB trains were running.
