Alright, here is video showing no lighting and dynamic light:
Dynamic:
Full: http://s31.postimg.org/p5qnkuee1/ue4_terrain_lighting_dynamic.png
Static (lightmaps only; “Use normal map for static lighting” option is on):
Full: http://s32.postimg.org/syck09g2r/ue4_terrain_lighting_static.png
Static (lightmaps only; “Use normal map for static lighting” option is off):
Full: http://s31.postimg.org/sbc6dw2mh/ue4_terrain_lighting_static2.png
If you open full images in two different tabs in your browser and look at them, the difference is quite noticeable.