Yes, going by points that is correct. However, the point system didn't change to devalue Masters comparatively when the finals went from best of 5 to best of 3, so points don't capture everything of significance.
If Djokovic achieved any 4 Majors in a row, I'd declare that the greatest 52-week period in ATP Open Era history, full stop (along with Laver's, if we are including him). Had he won the FO this year, it would have been the greatest season in the Open Era. If he had the same winning % or betteras Federer in 2006, then in my mind you could argue that 2015 Djoko > 2006 Fed.
In the 80s, the AO wasn't considered important unless you won all of the other Majors first; otherwise, it was insignificant. That is why McEnroe's 1984 season still needs to be considered (I disagree with the article on dismissing it). Also, I remember reading that in the 70s and 80s, prize money won was considered perhaps the most prestigious factor. This actually has some appeal to it. So what happens if we compare players through history by looking at how much prize money they won, adjusting for average year-over-year inflation in aggregate prize-money awarded to all players in total?