I have a feeling it won't stay on her being an underdog by fight-time. To be honest though, these lines guys are sometimes nutso bananas. Other times they have the inside scoop on tough camps or tough weight-cuts. So you really can never know for sure. We saw how wrong they were on Calderwood. I called my guy and said, "that line needs to be halved at least!" because his Casino was giving -850 to Calderwood and +620 for Moroz. They didn't listen. Took a bath on that one.
(And before I sound too gloaty, I told him in the same conversation that I thought the Baczynski line was wrong on the O/U because the American-Pol was going to grind the first two rounds as best he could, and lose a decision..... so I'm only smart half the time)
Anyway, The line for Herrig is favorable enough that I was willing to put down my standard investment. Any more and I would have been concerned there was an injury or people knew something I didn't. I believe linesmakers see her judo throws and subs from the bottom as the asset. But Herrig, IMO, has stronger takedowns, better top control, and generally more strength/power. In my eyes, Herrig just has more ways to win and a straight-line to the victory. And since I don't like Herrig in general, I know that's a sincere perspective. So I was comfortable at the + line and wouldn't wait any longer for it to move around IF you're going to bet on her anyway.