As far as I know, Uncle B was sent to a hospital due to shrapnel on two different occasions. On one of these occasions, he was to be sent to a replacement depot on release from the hospital, but disobeyed orders and hitchhiked back to his unit. He was court-martialed, lost a stripe and was put back into the line.
His explanation was twofold: he and his buddies had already learned the ropes and took care of each other, therefore he had a much better chance of survival; it was also "home" (such as it was). By that time, rank meant nothing to him.
Mr. niteowl77
Repple Depple - The GI’s hated it and with good reason but there were some good points to it.
Good discussions here on Repple Depple:
http://www.ww2f.com/topic/13262-us-army-repple-depple-system/
http://www.armchairgeneral.com/forums/showthread.php?t=90396
http://en.wikipedia.org/wiki/Replacement_depot