yes
I in no way approve of crossfit though
Why?.. My wife lost like 5 kg doing it, and she says it's more fun than other exercise. She did that "starting strength" program for almost a year, but got very bored with it in the end. Zumba and such didn't do anything for her, since it wasn't intense enough. Oh, and once she attended a kick-boxing training, got paired with some whore, who told my wife that she don't know how to kick and that made her cry. When she told me about it back home, I though it was amusing, so i smiled a little, and that made her cry one more time :) Never happened with crossfit, she is scoring good time there, and is always in a good mood afterwards.
Basically what people are doing is doing as much reps in as little time as possible, while most of them don't even know the correct form for those exercises or even use techniques to make your exercise easier like 'butterfly pullups' (aka kip as much as possible and break your back). Have you ever looked at the crossfit games? Half of these 'professionals' do exactly the same. There are people falling with barbells on their head and stuff like that. Even if you are using good form, doing such big volumes in such small time windows will get you fucked up, especially if you have had problems with joints etc before.
I would upload vids from infinete elgintensity but his channel got taken down because of 'copyright' claims by crossfit, most of his vids aren't reuploaded yet. This gif comes from one of his vids, where a professional crossfit athlete performs 'pullups'. It's not only that they are probably very taxing for your back, they also just kip so much the whole pullup gets 200% easier.