The importance of the OJ to "break" the cleanse is to prepare the digestive tract for the incoming food that has to be digested.
If your digestive tract isn't properly prepared, the food isn't going to be digested very well and put a strain on the digestive process resulting in food rotting in your system.
Because the stomach didn't hurt, doesn't mean all is well.
There have been people that have reported on this forum of digestion problems due to "rushing" the "break" part of the cleanse.
If you dump food into an unprepared digestive tract, the body has to handle the food and also struggle to get the digestive ability in order.
Remember this tract has been being rinsed clean for some time. Toxins, salt water have removed the necessary stuff for digestion.
Plus the body hasn't been producing the necessary stuff for digestion because it hasn't needed it.
Not rushing the "break" part of the cleanse is as important as any other part of it.