He is tipping pitches, but his struggles go beyond that.
Here is what Merloni had to say about it:
As Merloni noted, when Rodriguez starts to lift his hands, if the hitter can see the thumb of his glove, Rodriguez is throwing a fastball or something hard. If the glove remains flat, it's a changeup. After he pointed it during Thursday's game, even my untrained eye could call about three-quarters of Rodriguez's pitches.