This reminds
me of 2 other things I was taught, when removing a pulley or
similar from a shaft. If using a puller tool, don't stand in line with
it. If it releases suddenly, it will fly off and hit you. For large
pullers and parts, broekn ribs, etc are a distinct possibility.
My brother broke his nose with the back of his own hand when a similar
assembly "let go" suddenly. He was working at eye-level vs
bench-level, but it's the same principle - don't stand with body parts
blocking the axis of removal.
I was horsing around with my brother when I was about 7 years old and he
was pulling his hand away from me when I suddenly let go. He gave
himself a bloody nose and knocked himself on his ass.
Peace... Sridhar