Dont always follow manufacturer's instructions...

The manufacturer's instructions on this PermaBase cement backer board says you can score and snap, yeah right, if you have a few extra sharp blades for your utility knife and dont mind going over your scoring cut 100 times. Much easier to get the circular saw and zip it right off. Slow progress, another piece of backer board goes down in the upstairs bath inbetween wrestling matches with Ev.