The key, in the Ty Van Burkleo school of hitting the Astros will be subject to in the final six weeks of the season, is repetition. The interim hitting coach was promoted Sunday to replace Mike Barnett, and shared a bit of his philosophy. “I’m a believer in having a consistent routine,” Van Burkleo said when asked about his emphasis on cage work vs. video work. “I like drill-specific, getting the body to feel what you’re trying to feel and creating good habits but not overdoing it.” Van Burkleo spent the majority of the past two seasons as Astros minor league hitting coordinator, actually taking Barnett’s vacated role when Barnett [.]