My view is colored by the fact that my kids births were decidely not bonding experiences. I'm glad that yours were, but your stupid rule implies that the woman having the baby isn't entitled to her choice. In my family paying the bills doesn't give me the right of domineering over my wife and I respect her wishes on things. If you had an ounce of literal skin in the game then I'd care about what your opinion.
If the mother in law won't act with the proper decorum then that should be taken into account, but if she will then the person going through a the experience should have more say than the husband sitting there doing nothing.