the no carb diet is actually a very bad thing. carbohydrates are part of the process of how the body burns fat, cutting them out of your diet will make it harder to burn calories with exercise.
Whaaaaaat?!

I'm sorry, but no. Minimal to low to no carb diets definitely work. I do it before events all the time. Granted the fat comes right back when I start eating regular again, and that it isn't healthy to sustain for more than, say 40 days or so, but it certainly works. For a lot of people too, not just me.
I'm not saying he should completely exterminate all carbs from his diet, but definitely lower it. Your rice idea is good, so as long as he makes sure its brown rice.
As for the person who said you can't lose weight by diet alone, yeah... You can. :/ Again, I'm not saying he should do that, or take any of the extreme measures, just that you shouldn't claim things impossible when they most certainly aren't.
Again to the OP, just to make it perfectly clear: I do NOT condone a carb free diet, or a no exercise weight loss method. My advice was given in my post.