Why wouldn't the blended ray+physics technique described in the article not work? I am imagining projecting a bunch of rays from the blade along the vector of t

Why wouldn't the blended ray+physics technique described in the article not work? I am imagining projecting a bunch of rays from the blade along the vector of travel each physics tick and using that to determine if a collision will occur during that tick. I've never tried to implement anything like that, so I am curious where that might Fail.