TBT: Sorry, I thought it was a Maamar in Pirkei Avos . Maybe you can help me with identifying its source, since it definitely originates from our Sifrei Kodesh. And, I heard this Rabbeinu Yonah quoted from Shaarei Teshuva.
Mytake: The fact is, if someone has a serious issue of being inclined to dominate other people, then he will never be really helped out with modifying this middah unless he addresses it through therapy. Which Rosh Yeshiva has influence over his talmidim’s bad middos? Believe me, plenty of these masmidim w/ bad middos sit and learn mussar sefarim during mussar seder, and it barely does anything for them.