There was an article in pipes magazine some time ago. But I think it was also referring to pipe smoking. Anyway many cigar smokers are rated as non-smoker usually because they don't smoke a day or two before the medical evaluation, since cotinine (a nicotine metabolite) has a half-life of a little less than one day.
Which is still fine. Prudential will still give non-smoker plus rates even if you do test positive for cotinine and many carriers will allow you to admit to occasional cigar usage as long as you test negative.