I think you're right, when I watched Limitless again after trying Modafinil, it did seem like the writer or the director had tried it before, and then enhanced it for entertainment purposes.
I think it may actually help someone with an addictive personality, the reason being is that it is not a physically addictive substance, and you can lose yourself in whatever you're doing at the time.
So you end up forgetting about your other cravings, be they cigarettes, hash, or whatever. But as you properly pointed out, the key is research, research, and more research :-)
Thank you for your comments!