That article is deceptive. The title says that Rafa is "in extreme doubt for Melbourne," but Rafa himself said nothing of the sort and it seems entirely attention-seeking conjecture on the part of the article's author.
As for that full schedule, I wonder how much the #1 ranking influences Rafa's thinking. He's at 160 weeks and needs 40 more to reach the "200 Club" (Roger, Sampras, Lendl, Connors, Djokovic). While it isn't the most important benchmark it is a rather nice one. He'll coast as #1 for most of the year if he doesn't get hurt.