Yes, I think that data-based decision making in sales creates maximum opportunity for profits in all cases, because looking at data makes people focus on what the best opportunities are. Looking at data, people are not making decisions emotionally. They can focus on what has proven to have the best results.
Data based decision making is not enough to create profit in all cases because ultimately businesses must more and more businesses will adopt it. At a certain point, some businesses will not recoup the cost to invest in such programs and it will be to their detriment. And as more and more businesses invest in such software, it will level the playing field for said companies.
Data is good for analysis but not for predictions and future planning. It may give you an edge or help you to identify a developing trend but I don't think you can 100% rely on data to maximize opportunities for profit. Sometimes you will have to go against the data or at least not trust it completely.
I don't think you can judge for anything that is due for human error. There are trends and you can put out projections,but in the long run its impossible to find out what is going to happen down the road. The human race changes its mind way too much, and too often.