From my experience, a lot of subs don't know what they can handle - especially if they are new. I've had newbies think caning looked like the most incredible thing on film and with the first fall of the rattan, they use a safe word.

Making someone push through something that is not what they expected is usually not a good idea. There have been a handful of times when I have not honored a safe word, but it has been with subs I knew REALLY well and knew they needed to be pushed. These situations have been generally amazing and their trust in me has gone up because of the experience, not down. Sometimes Dommy knows best.