I must agree with Hood
Although you don't think you are homing, you must by definition, tell the machine where it is in relation to the workpiece before you start machining. That is homing in the same way as running to the end of the limits and touching a switch.
Because Mach can use limit switches as homing switches, there seems to be a misconception that home switches MUST be in some inconvenient place. Depending on the type of switch, you can have the homing swtich right in the middle of the machine.
As I said above, I use a laser shining on a detector, it is accurate to 2/10 of a thou. I have several detectors on a bar, and can line up to which one I wish, depending on the job in hand.
Even without homing switches, you can set your soft limits up inboard of your physical limit switches. Soft limits run in Machine Co-ordinates, not program co-ordinates, so therefore once set should guard the ends of your machine. Provided you do not then mess about with your machine co-ordinates you should be alright.