Personally, I would treat the professional tour as a completely separate tour from the amatuer one, simply because players who played on one tour couldn't play on the other. This doesn't invalidate either tour.
The comparisons between both of the above tours reminds me a bit of the comparison between the majors and the Olympic tennis events. Some commentators are arguing that the Olympic tennis tournament should be raised to the level of a major. However, this is a rather strange argument, given that the Olympics are held only once every four years. Also, there were no official tennis events at the Olympic games between the years 1924 and 1988. In addition, the Olympic tennis events are held over just one week or so and have smaller draws than the majors. So, all in all, the Olympic tennis events are not nearly on a par with the four majors, despite the undoubted prestige of an Olympic medal.