FT, you're right to be wary of people on the internet :)
As it happens, though, I have been here for years, and MN certainly know who I am. I am a breastfeeding counsellor with NCT and I have higher (non-medical) science-related and breastfeeding education related qualifications (I don't want to go into detail as I prefer not to out myself, even to close colleagues).
NCT has no views on burping - this is my own personal lack of certainty on display here. You can trust I know what I am talking about when I say I think there is room for doubt about most babies being in pain if they are not winded, and you can also trust I know sufficient about anatomy and physiology to make me doubtful that blowing on a baby's skin will make air in the stomach rise.
I've tried to be fairly light-hearted and show my scepticism mildly, and to challenge people (a bit) to think, so they may be less likely to be dogmatic about these things. I think it's fascinating that people have different experiences of babies' behaviours and responses, and I've already explained that active 'winding' won't do any harm (unless it's roughly done, of course) so of course people can please themselves.
But I don't know of any evidence that it is necessary, for most babies.
This has got some people really annoyed, for some reason.
Hope that explains things a bit better :)