Gopi Krishna, an Indian pandit and employee experienced quite a miserable failure in trying a Yoga experiment similar to that of Kirpal Singh, and probably because he could not cope with paternity, or uprightness.1 It was nearly at the same time, namely in the thirties of the last century that G. Krishna exercised himself in comparable yoga practices on his own, only to fall into a severe psychosis after several years of training.
Western psychiatrists at any rate, who had read his book on his experiences, could only come to that conclusion.2 G. Krishna was in desperate search for help.
No Yogi, nor Sant, nor Sat-Guru could help him. He saw blinding circling light, which constantly raged within him. He couldn't sleep, nor could he eat. He was close to suicide several times, until his confusion and purgatorial burning resided after months and years. It took long years for improvement to arise, which finally even lead to different states of glorification in which G. Krishna claimed the capability of speaking various languages. His constitution actually did improve. In later travels he met western scientists who were impressed by his personality, he also established an institute for Kundalini Yoga and wrote a book together with F. v. Weizsäcker, whom I mentioned above.3
Nevertheless, the term 'psychosis' was applicable for the years of confusion G. Krishna had gone through, though the spontaneous healing was extraordinary. He obviously was able to combine the Sūkshma aspect with the Stūhla aspect to achieve a unified language. Yet, Kirpal Singh had 'background'. The importance lies in which combinations the SHINES meets the SPEAKS. A good genetic foundation, a steadfast family, siblings and many other fortunate circumstances may very well have contributed to Kirpal Singh's audacious youthful experiments not being disastrous, while G. Krishna seemed to be incurably ill to begin with.
And so Kirpal Singh, quite in the sense of psychology, confirmed how important his brother's religious search and search for 'spirituality' was for him. Later on, of course, Kirpal Singh understood his circumstances to have been early influence of his master. Such just belongs to the mystical-mythical state of mind of and philosophy of Sant Mat.
1 Krishna, G., Kundalini, O.W. Barth Verlag (1972)
2 Personal note by Prof. Dr. P. Matussek, director of the Munich Max Planck Institute for Psychiatry at that time. Also, it was obvious through all of G. Krishna's narrations, that he was lost in exclusive imaginary signifiers, a risk in any meditation.
3 Krishna, G., Weizsäcker, F., Biologische Basis religiöser Erfahrung, O. W. Barth Verlag (1974)