When you had Jeff suddenly start understanding Pokemon language in Chapter 5, I knew you would have a reason for it handy. From the way you had the phenomenon described, it looks like it could make for a good way to distinguish the really good trainers. It could also be interesting to see other people's reactions to seeing Jeff holding conversations with his Pokemon.
Like everyone else, I see Corphish as a character who can definitely add some interesting things to this story. I was a little bugged at first by how he immediately went from an angry rampage to joking around with Jeff and Treecko after being captured; although, if I were hit by a bunch of burning embers for no reason, I'd be pretty ticked myself, even though I'm usually a pretty friendly guy, so I can see your reasoning for it. I liked how he was teasing Dustox during his battle, and I look forward to seeing more of that from him.
Your battle scenes have definitely improved between Chapters five and six, in my opinion. The varying uses that Jeff utilized for Bubblebeam was great, as was Treecko countering Mudkip's moves on his own instead of just standing still waiting for Jeff's orders. I especially liked that clotheslining at the end.
As DarkPersian said, the development with Kristie is certainly interesting, and with so many directions it can go, I look forward to see what happens next.
All in all, great couple of chapters, and I'll be back for the next one.
Pokemon X and Y:
Friend Code: 0061-0847-8548
Friend Safari: Emolga, Galvantula, Heliolisk
Seeking safaris: Currently None.
Looking for: Aggronite, Houndoomite, Mewtwoite Y, Charizardite X, Heracrossite, Groudon
Can provide: Pokerus, Any berry, Lucky Egg, Damp Rock, Light Clay, Light Ball, Heart Scale, Blazikenite, Many HA Pokemon, Most Pokemon only available through Pokebank, Some Legendaries.