I happened to see her show, which I usually don't watch. She was going to fry russet potatoes.
She cut a slice halfway through, then twisted the knife so the potato snapped off, creating a ragged edge on the slice and on the remaining potato. Then she did the same thing from various angles, creating irregular (though similarly sized) pieces of potato which each had at least one ragged edge.
She explained that this way, they don't stick together when being pan-fried. She only did them part-way, for a frittata. I imagine that if you did them longer, as for home fries, or oven-roasted them, the edges would be crisper and browner than those of standard slices. It's stay-out-of-the-kitchen weather where I live but I look forward to trying this out sometime soon.