You can't always rely on the wind. Most of the time the wind is variable anyway. This is just one reason why I control my scent. Better to be safe than sorry. I'm a firm believer in scent control, and just to add, it's not that expensive at all to be scent free for a hunting season. The stuff is not expensive. It never hurts to be extra cautious. I've killed many, many deer that were down wind of me. I don't believe I would have killed them if it weren't for me controlling my scent. This includes controlling my breath as best as possible. Everyone is going to get busted, but scent control, IMO, can lower the odds. Can you be 100% scent free? No way, but every little advantage helps.