I had this thought before V3 but I decided it wouldn't work because the track that doesn't move will sink, it's not the problem of the getting onto the track that's the problem, it's the getting off. The track'll still be at the same height coming off. Getting on might become a problem there as well, because the non-moving track will sink, and the intersection will still be at the right height since there's nothing on the intersection, which means that the intersection will now be higher than the track, you'll catch on the way in and catch on the way out.