As gods love flows in you kind of soften and become small, childlike in your chest.
This allows gods love to hit against or access small childlike emotions within yourself.
It helps you feel these.
This causes rapid softening and expansion of who you are as a person. You become more loving.
I suspect that the emotions that come up as one does this are, efficient, cost effective. For the smallest amount of effort, you see the greatest benefit.
Some people I observe who have learned to pray and do so regularly do not do anything like this and the positive change we see in them is far slower. There is no softening of their heart. They do receive benefits from the love, but without really growing much in their loving nature.
The positive change that can be observed in people using this 'shrinking' technique can be rapid and profound.