i think the point is that with the cleansing of the system, the body stops the cravings and it would be easier for him to quit.
i usually wont smoke cigarettes unless im already due for another cleanse and thats a sign that im due for one.
i usually smoke a lot of pot regardless though, i know its supposed to increase appetite and do all these other things but it helps keep me focused on my goal so...i think its all a mind thing.
cigarettes are really unhealthy though so i would suggest he try to stop and if he feels he absolutely needs one then to just smoke a little bit because some people cant handle abstaining from so much at once, its normal.