The article also takes a shot at LC:

"Irregularity is often accompanied by cramps, bloating, headache, backache
and tiredness, and this discomfort often leads low-carb dieters to seek
relief by taking fiber therapy, a convenient and effective way to boost
fiber intake in order to become regular."

IMHO the people who complain about constipation are not getting enough fat.
Tiredness only describes transition into or out of ketosis.  If the low
carber stays in ketosis, most report increased energy and reduced need for
sleep.

I think there may be a problem that some may be trying to force themselves
to go every day, as they did on high carbs.  If the body is allowed to do
what is natural, they may resolve the problem.

Dave
 http://health.groups.yahoo.com/group/LowCarbHighFat/