User blog comment:FairyRaven/Fairy Tail Chapter 425: Sabertooth X792, Review and Commentary/@comment-25111584-20150323191854/@comment-7418318-20150323195024

That he wouldn't tell anything a year ago makes absolute sense to me too.

F-Rogue's timeline was already changed by the seven Dragons making it through the Gate before it was closed and by present Rogue learning about his future self too. With those two things being different there was really no telling what else could change as a result.

Then there's also the possibility that Natsu blamed what F-Rogue said on his quite apparent insanity. I mean come on, in his place would you trust your friend or a mad-man who came from the future to become ruler of the world by burning half of it to cinders?

That he didn't tell Lucy what was going on is a different matter. I can understand why he didn't tell Lucy yet due to the rushing around and needing to act quick, but I do hope he'll tell Lucy soon. Leaving her in the dark until they stand before Gray would be careless to the point of cruelty.

I'm not so sure it'd be a problem if Gray defeated Natsu, depending on how it happens. For one thing Natsu might have problems going into full serious (i.e. killing intent or some equivalent) mode against Gray if he believes he's controlled. Then Gray could pull a guilt-trip on Natsu and confront him with how hurt Lucy was over his disappearance, which might cause Natsu to drop his guard for a moment in which Gray can punce and cause some bad damage to him. And finally there's the possibility that Natsu will become even stronger once E.N.D. is unsealed, which will set up a re-match on more even terms later.

I might turn out BS, but then it might not... we'll see.