assumptions based on slim to none evidence that "deep knee bends" would injure the competitor's knees.
I though I'd help out, so I remembered something I had read a couple of years ago & even managed to dig it out:
"This relentless myth arose in the 1950's and was based solely on one flawed study. A researcher in Texas, Dr. Carl Klein, was hell-bent on proving that deep knee bends (squats) were destructive to the knees, so he conducted a study with 100 lifters and 100 nonlifters. He put this little apparatus onto the knee and pushed laterally to see if it would move.
Pushing from the side like this showed ligament laxity. The gadget on the knee showed just how much it would bend. The problem with the study was that, before the subject got on the table, Dr. Klein would ask him whether or not he was a lifter. If the subject said yes, the good doctor would press harder on the apparatus! (One important reason why double-blind studies are more reliable!)
The results were flawed because of the researcher's bias and have never been repeated in subsequent studies. But the damaging data was out there: people were told that "squats were bad" and they still spread this myth today—50 years later!"
So, yeah people don't like to be "wrong". Hope this helps.