Enlightened teachers know this and this triggers two types of behavior on their part:
1. They try to provide you with the food and all the support you need to survive your time which is highly demanding both mentally and physically. So, in spite of being at the end of the food chain - you still get decent food. Or should I say - decent enough. This support is usually given in such a way that uchi-deshi is not aware of this and can not use this as a means of any mental support.
2. They will challenge you in EVERY possible way, both physically (technically, endurance and stamina challenges, sleep deprivation, alcohol overuse, you name it) and mentally (by scaring the living shit out of you, demanding that dojo is cleaner that hospital and by throwing all random tasks on him). And then, of course, there is a lot of pissing contests.
And then uchi-deshi is often asked impossible questions (like Zen koans) and given impossible tasks. What is the solution to such riddles? Well, every uchi-deshi eventually achieves his own way of dealing with this. What seems to be universally working is this:
Try to touch your ear with your tongue
Try to salivate from the corner of your mouth as much as possible
While doing all of the above try to say I love you to the person who gave you the impossible task/question
Try to hug/kiss the challenger:
Please note this will not work with EVERYBODY. Your aim as uchi-deshi is to survive and gain as much exposure as possible. Most challengers will just turn away with disgust. But then there are some who will just punch you in the guts/face/whatever. So you need to know who you are dealing with before you devise any strategy here (vide Sun Tzu).
And of course - unless your femur bone is broken to the point that it pierces the neck skin next to your collarbone...
What happens in dojo - stays in dojo