It's great that certain people find relief from not eating grains. I can't eat fruit or vege, and my safe foods are definitely simple and complex starches.
I think people need to be careful jumping to conclusions about grains. The mechanisms of inflammation are not necessarily as simple as presented by the cold data. Yes, Crohns people showed a reaction to the stimuli, that doesn't mean it causes flare ups, or that the pathway is that direct. I think you could put pretty much any food through a Crohnie and get an odd reaction.
The diet in that article (cabbage, sauerkraut, kimchi) would finish me!
all the best.