When I was 16/17 and playing, we had a coach that taught the catcher to step back with their back foot when attempting to throw out runners that was going to be successful in stealing a base. More than 1/2 the time, the catcher could make interference with the ump
This is a great video. So far, I've not been nailed for INT... but one coach thought I did (I was behind the SS)... but I've had a few times where it was close...