Yalgaar, it is all your projection, I have said what I have said and nothing more and nothing less. When I wrote that I never even thought of that asana as advanced as I have recently taught it to a lady in my class after six months of doing yoga. Why? Because I could see that her body could handle the asana, while there are others in my class whom I still hold back on teaching it to them as I can see they are nowhere near it to attempt the asana, they still need to do some more work though asana and pranayama.
What preparation do I imply? What is first and foremost in my mind when I talk about preparation is can the nervous system handle this abnormal position it is placed in? If the sense of proprioception (your sense of where you are in a given space) is lost then strength is also lost. Here the bridge pose is a good indication, but not always telling enough. I also look at how the student perform their back benders as they are telling if a student is ready or not.
Generally I also look at how the student perform in breathing exercises, especially how much control do they have of their diaphragm as those with poor control of the diaphragm most of the time are also overwhelmed by the muscular efforts of chakrasana.
I look at the strength of the student in the following areas: the abdominal muscles, the respiratory and pelvic diaphragms, the psoas, iliacus and rectus femoris as they all need to protect the lumbar region when this asana is performed. If there is a weakness in any of these, the student can hurt himself/herself and I usually will hold back and do a few months of more asanas to prepare those areas before I will ask the student to attempt the asana.
And than lastly I use my intuition to guide me. 
Just a last thought. Yalgaar, I don’t think we say to you don’t do it, but what I think most of us are saying it take it slow, three years before I found my teacher, Sri Durga Devi, I practiced yoga on my own. I learned bad habits and I also thought that I have researched everything properly. All we say is, Rome wasn’t build in one day, take it slow, one of the joys of yoga is the discovery, to do the child pose over and over and over and week after week to discover what it does to your body, mind, emotions and spirit. There are so many levels. Remember you have a whole lifetime ahead of you in which you can practice and develop.
I trust this sheds some light for you on your own practice and where you are.
