The issue with the slice zone from my perspective is how to best let traffic by you. It may be that there is no shoulder to the right so you can't pull over so keeping the lane blocked is the only real option but that can't be done forever if there is a lot of traffic. Typically I'll ride in the right tire track area to stop/slow down traffic but if nobody is coming towards me I'll then pull over to the slice zone as the car passes me. Sometimes they will pass really, really close, but by me pulling right just as they get to me I have extra space. If cars are approaching that make it unsafe for them to pass at all then I just keep the lane. I think one of the more dangerous times is when you are on a curve. They don't see you early and they may try to pass and then be forced to move back into you, but taking the lane is scary then because just a moment of inattentiveness on their part is all kinds of trouble. I am hyper careful on blind curves and keep the middle of the road then so I am smack dab in their field of vision and I remain ready to pull to the right hard. If traffic is doing 60mph that can be a very fast problem indeed.