yeah, in his instance. should've been clearer... here, i'll illustrate:

-bike 1 has an eai
-bike 2 has a phil
-bike 3 has a surly
-bike 3 is the quietest

in his situation, bike 3 isn't quiet because the cog is superior, but because the chainline on bike 3 is closer to 0 offset than on bike 1 or bike 2.

to illustrate this (kinda) further:
-bike 1a has a da
-bike 1b has an eai ss
-bikes 1a and 1b have identical chainlines
-bike 1b has a quieter drivetrain than bike 1a

this is because the cog is superior. all things equal, cog matters more. in his case, all things are not equal.

i may or may not have gone to far with this post.