Extreme Ukemi

Every dojo I have visited in Saigon seems to enjoy practicing extreme ukemi. Every class includes diving over multiple bodies in order to take a roll or a breakfall.

I know there are dojos that practice this in the U.S. but I have never practiced this way before and I am not sure if folks in the U.S. take it to such extremes. Here, it is common to leap over four or five bodies to take a breakfall or roll. I am not sure what the practical benefit of this is, but my real concern is diving and rolling over people who are standing bent over. I have to leap maybe four feet off the ground and come straight down on my extended hand. I am not comfortable with this. I feel like maybe other people are getting away with it because we are on a mat and because they are significantly lighter than I am (I am a very average 175 pounds, but people here are generally much lighter).

Today, I tried diving and rolling over three people standing bent. I bumped the first person and consequently did not quite make it. When I touched the mat my extended shoulder popped. It really hurt and is now extremely tender. I am not sure how bad it might really be.

I would really like to know what other people think of this sort of ukemi practice. Is it typical? Is it legitimate? Does anyone know a good YouTube video or other resource that might help me figure out how to do this before I severely injure myself?

I bought Bruce Bookman's Advanced Ukemi video hoping it would help. It had a lot of great ideas and techniques but unfortunately nothing on this sort of practice.