It may give you an energy boost and some claim great focus; however since it is a vaso-constrictor it limits flow of oxygen to muscles and any benefits gained from it would be severely overshadowed by this fact. It is a bad habit and should definetly be given up if he is serious about his goals and his health.
Caffeine is also a vaso constistor. Funny how it's in nearly every preworkout "pump" product. You'll probably be hard pressed to find many bbers/athletes who do not use caffiene.
IMO nicoteine has little to no negative effect on athletes. Unless of course theyre smoking. Sure long term use of smokeless tobacco is bad for your health. So is slamming caffiene preworkout and eating a pound of red meat daily.