i can't smoke spliffs anymore (weed + tobacco mix)... my high is totally garbage with the baccy in the mix. i can smoke a gram and be high as hell, but if i rolled a spliff with a gram of weed and .5g tobacco, i won't be nearly as high for some odd reason. i recently quit my pack-a-day smoking habit (cold turkey).... about 3 or so weeks ago. i'm not sure if that changes anything, but i used to chain smoke while high and just become even more buzzed. now mixing the two basically wastes the weed's effects for me. maybe your friend is the same?