I found that if I stay below 100g of carbs for an extended period of time, I get pretty backed up, even with daily kombucha and fermented pickles. After swinging up as high as 175g, I have settled into about 125g on average. I don't worry so much about carbs, per se, as just eating real foods and avoiding seed oils, legumes and grains.
12oz of potato (sweet or white) 4 days in a row seems to work better for me than any other laxative strategy I've tried. I just can't eat that much potato for days on end, because the noise and rumbling in my stomach and intestines gets really annoying.
I completely agree that you need to choose a way of eating that works for you, rather than trying to force yourself into someone else's mold. There are a number of different "diets" that are good jumping off points.
50yo, 5'3"
SW-195
CW-125, part calorie counting, part transition to primal
GW- Goals are no longer weight-related