Every hitter is going to go through struggles. I swear David Ortiz went o-fer-May a few years back and then hit 35 HRs and batted .340 from June-September. Of course every hitting coach has their certain method and style, but the very best coaches should always try to work with a certain players strengths. Once you get to this level, changing someone's entire approach and method just doesn't work with high success. MLB coaches aren't teaching players how to hit or how to pitch, they are teaching approach and helping to correct flaws when something gets out of synch. College coaches should be doing the same. There have been some insanely weird batting stances and swings through the years...Pete Rose and his one eyed backwards lean, Yaz's forward lean, Ichiro's softball slap hit style. These things worked for them and no one tried to change them. If the player comes in and can hit the better college pitching, then minimal coaching is needed, just observe and if things start going sideways, step in with some tips about what has changed in their approach.