Crikey. There are, I will be the first to admit, lots and lots of sticks (big and small) used against women in pregnancy and childbirth. I spend a fair amount of time on here arguing against them.
It never, ever occurred to me that a bit of 'try sitting on a birth ball and see if that helps' was one of them, though.
I do see your point to a degree, wahwah, re: empirical evidence. But, particularly where pregnancy and birth is concerned, there is always going to be LOADS of stuff that can never be 'proved', usually for ethical/logistical/sampling reasons. You can't do RCTs on pregnant women in a lot of situations. Having said that, I think there is a trial somewhere about women who were given OFP advice against those who weren't, so I'll try and find it for you Not everything can be tested under lab conditions but it doesn't necessarily make it invalid advice.
Fwiw, I am a big fan of Jean Sutton and am of the opinion that OFP makes a lot of sense from a physiological perspective (and a historical one too, although perhaps less strongly).
If you ignored the advice about OFP and your labour was fine then, great - you were obviously someone who didn't need the advice! But if I see someone in a/n clinic whose baby is lying OP, I'll give them OFP advice in the hope it might do the trick. It's not 'some crazy agenda' - it's just something that might work, or it might not.
This is reminding me a little of the 'swallowing prostglandins' thread, you know...