I'm no MW, but to me this looks as though someone has taken this little gem right out of the PROMA study. (Pulled Right Out of My A...)
ROFL!

you can prep yourself to try not to 'push' as much as just let your body propel the baby out, KWIM?
Ah yes, that aspect I have trouble with. I tore both times, first time DS was epidural and forceps so I couldn't feel a thing.

Second time with DD, they told me to get up on the bed and start pushing and it felt completely unnatural, I did not have the urge to push. The midwife told me I sounded like I needed to push and I told her I felt constipated but had no real feeling that I wanted to start pushing...but they told me it was time. The OB then told me I wasn't pushing hard enough and so DD's head wound up half-crowning and I had to wait for the next contraction with her head half poking out and the OB telling me that if I'd pushed harder she would already be in my arms. Helpful...not. He told me afterwards that his wife never felt the urge to push either and she'd had 5 kids.

It was only 3 little stitches after DD though.

I actually asked my OB (new OB this time) about whether it was true some women just don't get the urge to push and she looked very dubious and said it was very rare and that they'd probably made me push before I was ready.

The idea of the contractions helping push the baby out is still something I simply don't "get" because I don't know what the urge to push feels like.