toughest and most important role on the court. Like a quarterback in a read-option offense, the success or failure of the offense depends on their ability to read (and guess) at what the defense will be doing.
He's most likely basing it on the in-game and in-practice decision making and chemistry (with hitters) he is seeing from Robbins-Hardy at this point in the season.
Seems to be working for him so far.