I was just thinking of Lucid Dreaming, which is the ability to conciously control your dreams - normally something experienced without the use of the concious mind. People have learned how to have lucid dreams at will.
The possobilities involved with the concious control of each and every bodily function are virtually limitless.
Take, for example, the control of pain by the concious mind:
Pain can be a useful function when you lean on a hot surface that is hot enough to be damaging to your skin, or when you break an arm. Without pain we may not be aware of the damage done, and any injury you recieve could be made worse over time without realising the damage done before it is too late.
But what about when a person falls from a twenty foot cliff. What use is it to your survival when you lay on the ground writhing in pain, with a higher risk of you going into shock, unable to control yourself. You may be a mile from the nearest road or town. The pain you would experience would be enough to stop you from getting yourself to a hospital. Just because you have one broken leg. With the concious control of pain, you could get onto your good leg and simply hop to somewhere where you could get the correct medical attention.
If you were to set your sleeve on fire by leaning on the cooker. You would normally run around, arms flailing screaming in agony as you slowly burned to death. If you had control over pain, you would be thinking with a rational mind. It would occur to you to take of the clothes that were burning and get to the nearest source of water.
There are a lot of other bodily functions that at some of the time could be considered simple irritations that have no real use. It would be useful if you could simply temporarily "switch them off".
Maybe I just sound totally insane, in which case you should ignore me completely and get on with not wasting your time in other topics.