Article 250.122(F), 2014 NEC: Let’s say you have 4 parallel circuits, consisting of single conductors in triangular configuration installed in cable tray. NEC says only one EGC is needed suffice for all four sets. I say this is inadequate and defer to the same scenario using 4 parallel circuits consisting of multiconductor cables in which case an individual EGC would be included. My rationale uses the same laws of physics governing magnetic flux, impedance and fault path, i.e. EGC must be in very close proximity to phase conductors in order to be effective. I believe this article needs to be revised to include a separate EGC for each set of parallel single conductor bundles. Only problem is, I don't have the capability to produce the math in order to prove my point.