It was not entirely fair to cite another person's reaction to a teaching method which is at odds with my own. Every teacher, no matter what the approach, will experience children who cry or complain for reasons not all that easy to figure out.
My reliance on gross-motor training--i.e., whole body responses to sound rather than fingers-first--is unfamiliar to most children aged 6 through 11. It may make them uncomfortable to contemplate making the transition between a mostly sitting school day and coming to music, where a different orientation is called for. As it is the transition that yields the discomfort they are more likely to complain to parents than to react negatively while with me: In fact they clearly enjoy the time we spend together. Good communication with parents is key to figuring this out and supporting the child through the process.
Two memorable instances of real tears come to mind: An 8-year-old crying at a minor 6th in a Bach minuet, the relative dissonance unbearable to her sensitive ear; an adult foreign student crying during a coaching on Schubert because she realized that the more she studied the clearer it became that she did not feel comfortable with European classical music.