I think one of the most important things to realize in the ever-long journey towards growth is the dynamic relationship between fear and love within humans. There is an intertwined dualism between the two, in that, when someone is filled with love, there is an absence of fear and accompanying emotions and vice-versa, when someone is filled with fear, there is an absence of love and positive emotion. They are not like two separate things to be experienced but conjoined like a balance scale that make up our state of being. I first realized this in my own meditation practice where the objective was to constantly exert an effort to feel love towards everything for a few hours. Eventually, I got the sensation that, "my heart", was filled to the brim with positivity and because of that, there was no room for negative emotions to enter. What followed was a change in my attitude of life and my behavior went from aversion to fear to engagement with it due to excitement and confidence. The voice in your head telling you that you can't do this, or this will go bad was no longer there as thoughts are only a reflection of your mood, fear, or inner being. So I think Tom's dualistic metaphor of fear and love is apt because I completely felt a duality in two different states and the spectrum of emotion they existed in.
So in this sense, I don't think you necessarily have to tackle fears on an individual level. Growth can happen holistically and the rest can follow. However, tackling fears individually leads to the same thing anyway as it is a tool for growth.
In putting MBT teachings into practical application, I find three important aspects to focus on:
Awareness: Awareness is they key to change and development. Unlike animals, we are not bound to animalistic drives and impulses because we have a higher level of cognition that allows for awareness. We are not doomed to repeat behaviors because our awareness allows us to interpret what presupposes our behavior or action and then we can reject it or choose action in the aim of a new intent. Because of our level of awareness, we can almost entirely reject our animalistic hard-wiring which represents a great deal of potentiality in evolution through our ability to choose our intent and our action and consequently our development path. However, if we are not exercising awareness, we are living as animals do and are bound to repeat behavior and get stuck. There must always be a conscious effort to practice awareness in our daily life because it expands our set of options when reacting to situations and allows us to program ourselves. Growth is always an upstream battle and if one is not evolving, they are devolving.
"Opening the heart": What I mean by this metaphor is to bring emergence to the being-level state in a certain kind of way. Many people on this forum and in daily life, including me, live in a very left-brained thought processed way of experiencing reality. It is not enough to rationalize Tom's teachings, love does not care about rationalization. As Tom has said, all growth happens at the being-level. When we are in the left-brained thought process, we are essentially putting up an intellectual wall towards everything that filters what gets interpreted into you and what gets expressed outwardly in relation. We have to integrate being level interaction with the world for true growth. In order to do this, love must be practiced in it's expressive form. We have to exercise emotions such as love, compassion, empathy etc as it creates a relationship with all things and the player learns not to make it about themselves. This is not as simple as it seems because there are levels to it. Ask an average person to practice love and their love will be average and confined. I believe these emotions need to be activated and channels need to be opened. In this day and age particularly, people live their lives with these emotions or expressions dormant. Emotional release and emotional connection are very important as they are reflections of the being level state and being level interactions. Many people, for example, practice ecstatic poetry from the likes of Rumi and find a new appreciation for life and a new propensity for love they did not previously have.
Keeping Perspective: This one goes with the other two. Fear, ego, and belief all limit our perspective and consequently our understanding. We get so locked into habitual patterns of daily life that we start to see life only in one light and get stuck in particular modes of thought. If you've ever engaged in a petty, hostile interaction or argument with someone at work where you've spent the day dwelling on it and had it ruin your mood, and then had a incident where your loved on ended up in an accident or hospitalized the same day, you might then become completely disinterested or forgiving towards that person at work. Why is that? Because the incident with a loved one gave perspective on life and dissolved the egoic mode you were previously operating with. You realize the argument is really not as important as you made it out to be, your loved one's well-being is. In order to engage with that hostile attitude and argument again, you would once again have to limit your perspective. In that way, expanding and keeping perspective is liberation from the ego. When you get offended from someone, it is your ego, your individual and constructed sense of identity that is challenged which invokes a hostile, adrenal response. In an expanded perspective of what life is, you see the situation for what it is beyond yourself.
Hope that helps.