Yes, but you don't quite understand. I tallied all the tournaments and points that they had after RG all the way to after the AO as the base.
This is why Murray is still a greater threat than Djoko, for the simple reason that he piled on more points from June of last year, to February of this year. Djoko, on the other hand, has a substantial amount his points based on this section of the season. Now when I award both of them their maximums, Djokovic gets zero benefits for doing well last year in these tournaments, and Murray gets rewarded for doing poorly, even though they receive the exactly same thing, a win.
No, Murray is not a bigger threat than Djokovic. Obviously it is more likely Djokovic with Nadal kind of uncertain on clay season can go on winning 2 master series and RG, in which case he will probably end up as nr1 after RG.
Murray wont win a clay master series and wont win RG and therefor no matter what kind of math you are working with is no big threat to Federer's nr1 record.
Only Djokovic and Nadal have the potential to have crazy clay seasons while Federer with some early loses in the big ones would be in danger of not breaking the record.