Measuring from the underside results in extra inch in length. If she measured from the topside she will get an inch less in length. Check it yourself. The cock extends an inch past the pubic bone when measured from the underside.
I used to love Megan til I google searched her name and found out she was recently arrested for extreme animal cruelty in videos. The details are awful. Shes a sick and horrible person and I can't even see her face without being disgusted. Boycott her videos!