What you say may apply to everybody because everybody has things in him which conflict with the Yoga. Logical conclusion: Nobody should try anything in which anybody has failed or in which there is a possibility of failure! I am afraid most human activities would stop on that principle except, (food, sleep and sex) and perhaps only the first two. But after all not even these – for people die in their sleep and others die of their food by poison, indigestion or otherwise. So to be safe one must neither eat, sleep nor do anything else – much less do Yoga. Q.E.D.
What you say may apply to everybody because everybody has things in him which conflict with the Yoga. Logical conclusion: Nobody should try anything in which anybody has failed or in which there is a possibility of failure! I am afraid most human activities would stop on that principle except, 
(food, sleep and sex) and perhaps only the first two. But after all not even these – for people die in their sleep and others die of their food by poison, indigestion or otherwise. So to be safe one must neither eat, sleep nor do anything else – much less do Yoga. Q.E.D.