Don't get me wrong, crying in a sadistic session can be cathartic (it's just not the same as broken). If you're interested in crying in session, I hope you get there. As far as being held back by marks, there are ways around that. For example, ball busting rarely causes marks on me if the impact is thuddy, but (at least for me) its one of the most painful tortures, especially if you are restrained without a way to curl up. I've certainly cried in session from heavy ball busting with no visible marks (but certainly some soreness the next day or so). Ball squeezing also typically doesn't leave marks but can be certainly be excruciating enough to lead to tears.

But of course, everyone is different when it comes to actually crying. So many variables have to be right and the connection with the Sadist needs to be strong. It helps if it's an explicit common goal, that she wants you to cry for her and you want to get there (It's never good to surprise a Domme with tears, discuss it first). For me, it has some similarities to an orgasm. You know how you can get that feeling that your on the road to an orgasm and you just have to let go a little for it to roll over you? It's similar for crying in a session. There comes a point where you realize it's just a little down the road and you just have to let go and the tears will come. And while orgasm is a sexual release, crying can be an emotional release just as powerful. For me, the best sessions involve both types of release and it leaves me with such a profound sense of calm. That's the feeling that I chase in sessions again and again.