Depending on the version of maya your using the sub-d problems in MR are sorted, I cant remember which version it is that dosnet care anymore about the sub-d's but it could be either 8.5 or 2008.
But your right John, if its a backgorund then there should be no probs, of there is then just making the normals soft should do the trick.
"No pressure, no diamonds" Thomas Carlyle