WOW - Use the L word and watch out...
Didn't mean to offend, but recently had someone tell me that fishing MC the same way over a dropped grid cieling was OK. When I said, "Man, thats a lot of tiles to open..." They looked at me like I was nuts, I then looked at them like they were nuts.
It (a grid ceiling) is designed that way for this express purpose...
IMO pipe is an easier method too. One caddy per 10', usually in the same tile you're putting the coupling in. (And support wire too, if ness. Think about how many of those you need for flex, or MC?)
Go as the crow flies, and it don't need to pretty, just solid. Straight pulls easier... Duck and run....