Do you ever split roots with your methods?

Short answer is "nope" because it can't happen with this technique.
One of the neatest things about a cement technique is the cement is injected with a syringe.
Thus there is no "log-splitter" pluggers ever used and the cement is simply flowed in.
Furthermore, with the Multi_Mode version of the Precision Endo Syringe or more recently the Precision Endo Obturating Cartridge Syringe we can now control the flow to +- 0.00009 cc