Huh, usually they do it the other way around, sculpt the model, then retopo (based on the complexity via hand/automaticaly (computers just can't beat a good artist)), then baking all the maps.
Bump, Perralax, Normalmaps etc. are great to fake geometry details. However the closer you get to them, the more the illusion gets
broken (note how the bricks look nice an all but the sharper the angle gets to a polygon, the flatter the cube looks).
Tessellation is a great workaround, however the computer doesn't know where extra geometry is needed and just throws extra polygons everywhere. These then get displaced via a texture with black and white values that tell the pc to put then higher/lower/at the same height as the others.
While this takes less processing power then real geometry, it takes a hit that is to big for consoles and you usually don't see it there.
(Waits for unlimeted detail)