I may have oversimplified the rules but when I looked at wiring methods supported above a "T"bar, I just satisfied myself that the load was being carried by a support method other than what the "T"bar guy installed to hold up his stuff. If there appeared to be a different kind of wire than the ceiling support and that was carrying the electrical it was OK with me.
There is a lot of "judgement call" here.
I was really just happy to see it was't laying on the ceiling tile but I did try to enforce the intent of the code.
Before they tightened up this article there was really a lot of abuse in suspended ceilings, like MC daisy chained between the layins, with no support at all.
