A good score is pretty much the only solution, and even then it may not be clean.
The problem with a lot of coated stocks is that even if you fold with the grain, the coating itself cracks.
Offset presses or anything using a wet ink kind of bypasses the issue because the ink soaks into the paper and the coating. With dry, toner based presses, the color is just sitting on top of the coating. So when that coating (or even the top layer of a heavy uncoated stock) cracks in a fold it's just revealing the untouched paper fibers under the print.
