That's just not true.
Ranking points for majors and Masters 1000 series (of which he won two) are significantly more than the "lesser" tournaments which keep people from doing what you're suggesting. At least in the top spots.
And Murray/Djokovic were IN one of the two 500's he won (he beat Murray in the final).
Plus he's been in the semis or better of the last four Grand Slams sooo...he hasn't won a slam in the last year but he's been consistently great and he deserves every single bit of that number one ranking.
Which pains me to say since Nadal will be #4 soon but it's almost not even arguable, especially since he beat Djokovic to get there.
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Congratulations to Rafael Nadal on a Career Golden Slam. - The Mana Sword