If you're asking this question then no, you should not.
Rolkur is not something to be played with lightly. Although I 100% don't feel that it is at all necessary to jam a horses head into its chest and make its nose become nearly parallel with the ground in rolkur, I do see and use the benefits of some work of low, deep and round (the true version in which the horse is ridde n very softly forward into a deeper outline to work different muscle groups, and occasionally to bring a spooky or naughty horses brain back into fear).
In either option, you need to be an experienced rider with a good feel. The fact that you asked this questions tells me that you are not.
My advice, get yourself a good instructor rather than trying to copy risky techniques to shortcut your mates training. Posted via Mobile Device