I was talking to a bike shop owner that was in his 50's. I asked him about brifters and I was surprised at what he said. It was his opinion that the main advantage of the brifter was for racing while in team events. He said that some of the teams had riders that were out to take down other teams top riders by intentionally breaking and causing crashes. The brifter allows the rider to be in a position to shift and break without having to move their hands so that they can ride more defensively.
He went on to say that he preferred down tube shifters because he does not race and no matter what hand position he is using while riding he can just drop his hand to the shifter easily. He also said that most riders when shifting brifters want both hands at the same location on their bars while shifting. Maybe this is because there is a chance that the brake might be accidentally applied.
I have only used down tube shifters and have never had my hands on a brifter so I am wondering if any of the above information is even close to being correct. It sure seems like most want brifters on their bikes.