I always thought that the 1011 was engineered better than the 10 simply because the 1011 #2 has an S-duct.

I'm not an engineer, but was told by structure mechanic, who worked in the Palmdale plant in where it was built that the S-duct puts the thrust of all three engines on one plane. Unlike the 10, the #2 is located above the 1 and 3 engines.