User blog comment:B214/Chapter 499: Gray & Juvia/@comment-7418318-20160829143550/@comment-2214433-20160829151801

If Juvia's water body was automatical, there would be no need for Gray to jump in and shield her against the mini dragons. :^)

Nah, that's really just an excuse. In reality, I'd have to say that Mashima takes the easy way out and forgets abilities that'd make it easy to get out of the situation at hand. But a part of me still wants to think that this isn't the case...