What exactly does it mean to have "stabilized" at a particular level of awareness? It means that awareness of a specific area no longer occurs at the expense of space. I may need focused, effortful concentration at first (complete with tension/contraction/resistance), where it's all I can do just to not lose track of the frequency I'm tuning into. After a while though, space starts to open up and I can look around a little bit without losing track. I can bring more of the surrounding context into my awareness without losing the original frequency. More of my system can relax; a new competency relieves it from all-hands-on-deck mode. As with learning to ride a bike, I know I have stabilized when I can enjoy the scenery without falling over.