I would not recommend snapping anything on your plant, ever. Only remove parts carefully and with a disinfected and very sharp razor blade. Can you tie the tallest tops to the side? This will have the added benefit of allowing light to reach the lower branches. Are you in flowering or veg? If you are in veg then you can experiment with "topping" but I would only take tops off of tallest branches if you are in veg and have time to let them recover before you plan to flower. Otherwise, just like pruning an apple or cherry tree too early, you are just going to be removing a budsite that has already begun to flower or is just about to.
pics would be very helpful