Hi YB:
Silent Self (inner silence, witness), once cultivated, is abiding whether there are thoughts or not. So it is not only a condition of no-thinking, though it does give the mind a foundation in stillness, which tends to calm the mind. It is also the prerequisite for self-inquiry as described in the new AYP book on that subject.
But, no, Silent Self does not mean a condition of no thinking. Rather, it is the ground state of inspired and illuminated thinking, which is what perhaps the others are describing. Same condition, different words.
However, it is misleading to present Silent Self as a condition of "no thinking." Then people get the idea that enlightenment is about killing thinking (and desires). This is not true. Not any more true than yoga being about sitting in a yoga pose. The field of play is beyond such external things, including our thoughts and feelings. Effective yoga practices cultivate the witness without getting into a wrestling match with the mind, emotions or body. It is about going beyond all that and coming back in as Silent Self, even as all the external stuff is continuing.
Yes, once we have been meditating for a while, abiding inner silence will be there even as purification and opening are underway. At some point we begin to see our thoughts as objects separate from our Silent Self, and this is where real self-inquiry begins. It is the beginning of being able to discriminate between Self and all objects, including our thoughts, emotions, the physical environment, and the ongoing purification and opening that are occurring within us. From this point on, kundalini becomes a cakewalk, along with the rest of life.
Silence with noise -- not "noisy silence."
This is why Silent Self (the witness) is at the heart of all spiritual progress. Until we cultivate that, we will continue to be identified with external objects, beginning with our own thoughts. But it isn't our thoughts we have to get rid of. It is abiding Silent Self (witness) that we want to add. That is the result the sages are describing in one way or other, depending on their current experience and personal perspective on how they got to that condition themselves (if they know).
The real question is: How can everyone bring about this condition in themselves quickly and safely?
It is one thing to talk about enlightenment. And something else entirely to be cultivating it by effective means. Then all the answers will be coming from within, and we can give our own description. I am looking forward to hearing about it from more and more people. Bring it on!
The guru is in you.