What's worse, to move down or to move up in weight violently?

Obviously Down if it's 2 three divisions.
Dawson. DLH, Mosley all went up and down.
Up is terrible when you do a 3 division jump withing 2 fights, Marquez. Jossesito Lopez didn't jump 3 but 2 still got destroyed.

 

97% of boxers fight at a weight below its normal comfortable weight, hence they choose to weigh in at the threshold of the weight limit and come in way above the weight class they are supposed to fight. just saying.

 

Droppin in weight is more dangerous. You're just plain weaker doin that as opposed to goin up in weight.

 

It depends on the jump. A welterweight going up to fight a heavyweight would be very very bad for one's health. But not so much for a welterweight going down to lightweight.

I'd say, it is better to stick with your natural weight.