Keep in mind, she's been in the show now for a few weeks--she's had time to adjust and she has probably improved a bit. Those videos are from opening night or so, aren't they? Don't judge her performance from the video.
I'm not a Haylie fan--AT all, but it's not fair to judge performances from video clips (especially ones that short). When I watched the video clip of Mylinda Hull as Jolene in DRS on broadway.com, I was about to cry. I couldn't believe I was seeing her that night--she looked so horrible, but she turned out to be one of my favorite new cast members.
"If it walks like a Parks, if it wobbles like a Parks, then it's definitely fat and nobody loves it." --MA