Now that I think about it, I stopped thinking about cycles a while ago and started thinking in breakthroughs. What I mean is I have an objective or a purpose for using a product and I use it till I accomplish that goal. Until I break through whatever limitation or problem Im experiencing at the moment, until I reach higher grounds.
Stage 1 purpose was to heal my heart from a nasty break up.
I did 2 cycles of st 1, because thats what it took me to heal the wounds of the break up, the pain, the sadness, the anger, etc.
Stage 2 purpose was to be at peace with being alone.
I did 1 cycle of st2, because thats what it took me to heal from the anxiety and be at peace with the idea of being alone.
Stage 3 purpose, is to be free of the past and learn to love life, to be open to higher quality love.
About loop duration, I wish I had a rationale to explain, but I dont think I have one, I could avoid an answer by saying is a purely intuitive decision, but Im not sure about it either.
I start at 1 minute loops and I increase the timing as Im going deeper into the issue at hand, usually I stop when I reach 3:30 minutes at some point of the process, IIRC 4 minutes is the maximum Ive done in a long time.
Basically theres a process, a strategy, but Im unaware of the whyās, I trust results and the strategy works, so I roll with it.