I havent read every reply to this thread but the ones i did read most of them did not talk about push/fold ranges, some were hinting at the topic but most did not mention at all.
When you get to the point in a tournament where you have 20 BB or less, which happens quite often if you tend to play more mtts then anything else, then you need to have solid push/fold ranges for every position on the table. Granted you dont always have to be shoving pre flop if you have 20BB but with a low M, which is your stack in relation to the blinds & antes PF, you need to maximize your fold
equity by open shoving, stealing, restealing, etc.
It is true that when called you have to have some luck and have your hand hold up or if calling a shove gaving your hand beat villans shove and many times will end with you busting out but if your goal is to win the tourney then this is the risk you have to take, a calculated risk any way. If your gial is just to make it ITM then you can sit araound and wait for premium hands to shove while the blinds steadily devour your stack.
Google push/fold ranges and you will find plenty of good information and how to develop your own based on your p5laying style. I will say that most of the push/fold charts out there are mathmatically proven for short stacks.