Dismissing Schweizer’s stride as flawed but ‘it works for her’ is missing the point. She has run some good times and has a very strong collegiate resume. That said, her biomechanics are absolutely holding her back from realizing further potential and will make it difficult for her to stay healthy over the long term.
Watch her run from the side profile and look closely at: upper body angle, pelvic tilt, stride length and foot strike (among othe things). Karissa works against her own body in order to propel herself forward. It’s amazing what she has gotten out of her running style thus far.
Hopefully she will find a coach willing to tighten things up mechanically and let her engine work with a more efficient running form.