Will his environment for his one year sentence be safe? Will he be able to make use of his time reading books etc. Could he be raped? Will the environment and situation break him down? How will his experience be? I
You are speaking to someone that did 66 months. A one-year sentence is considered not too rigid or hard on the inmate. Time will fly by once they get into a routine. He will be able to read magazines and books to his heart's desire as he has plenty of idle time.
Prison rape, although evident in some places, one-year sentence inmates are normally not in the type of facility where this is more likely to happen. Short-timers are often in a minimum security prison and the inmates there are looking towards the door and making trouble is last on their agenda.
As far as "breaking him down", that doesn't happen often in a one year sentence. Once he gets into a routine, he'll be almost out-the-door. There isn't much time contemplating a long bid on the inside. You would hope he learns his lesson (whatever that might be), but some offenders with light sentences don't get it the first time. If he is the type guy to keep busy, his experience will be enlightening and hopefully impactful enough that he doesn't go back after this short stay.