Now in yeshiva I learned a certain amount of Gemara and Tenach (Old Testament). But to get a good idea of what the Torah actually requires of me I found I was not really understanding at all until I learned Musar.
The thing I gained from Musar was to get a good idea of the basic worldview of Torah--that is: what the Torah consider important.[Also the ספר החינוך was a great help in that direction.]
There is however a question on this system because sometimes people that are "משגיחים" "mashgichim" מנהלים רוחניים "the spiritual adviser in the yeshiva" are not people that represent the ideals of Musar very well. In fact often it is those people that specifically give Musar and all yehivas a bad name.
I wish I had an answer for this dilemma. But at least for myself I consider Musar to be the way and the path to the Tree of Life because through it I can understand at least more or less what is is that God requires of me.
Just for the record the actual Musar books that I liked the most were the Mediaeval Books: חובות לבבות Obligations of the Heart, שערי תשובה. אורחות צדיקים, נפש החיים ספר היראה המתיחס לרבינו תם, אור ישראל ע''י רב יצחק בלזר תלמיד רב ישראל סלנטר
(Musar tends to emphasize fear and love of God and good character which it sees as the most essential and important aspects of the Torah. )
Once I discovered musar I tried to get my actions to fit. Part of the problem for me was the message was not always clear. That is the yeshiva path seemed different to some degree. A later problem for me was the religious world really did not seem kosher at all.