There is perhaps a connection. Nicotine improves chess skills. It improves concentration and calms the nerves. Today, people are going over to e-cigarettes, instead. It is known as vaping, instead of smoking. The vapour made out of an e-cigarette is the result of vaporizing an e-liquid. The e-liquid (e-juice) vapour provides the smoking sensation and taste. The e-liquid base is composed by two ingredients - propylene glycol (PG) and vegetable glycerin (VG). Both of them are vaporizing at around 60°C. They are considered harmless. To this, nicotine, flavour, and small amounts of purified water and alcohol are added. Vaping doesn't produce smoke, only a harmless vapour. The vegetable glycerin turns into carbon dioxide and water, while the propylene glycol is wholly converted to energy in the body. There is hardly any smell. If anything, it smells good.
I theorize that vaping increases the chess playing strength by, perhaps, 40 Elo points, on average. In the UK, there is a call to allow vaping in pubs. I think we will soon see the same issue raised in chess clubs. I know that vapers would very much like to vape at the board. I am myself a vaper, and I just wanted to inform you about this issue, and to put it on the agenda.

More information here:
http://vapegrl.com/
M. Winther