Actually jaggedthistle the only thing that is utter, utter bollocks is your rather sactimonious attitude.
My research included actually speaking to a dietician (who explained the whole weaning before 6 months/BF WHO issue)and Health Visitor, reviewing the British, American and Australian dietetic associations position on weaning, and where possible the actual scientific studies mentioned within.
The British Dietetic Associations position on weaning is that it should occur somewhere between 4-6 months depending on the child but not before 17 weeks. They find no evidence which supports the suggestions that weaning before 6 months causes harm to babies.
I suggest you have a read of it here:
www.bda.uk.com/publications/statements/PositionStatementWeaning.pdf
You are correct in that the individual child must be ready to begin solids and the signs are as you describe, however i was not suggesting otherwise. If a 4 month old is sitting up supported, has lost the tounge thrust reflex and is interested in solid food there is no reason not to let them progress onto solids just becuase they are not yet 6 months old.
In some cultures babies are weaned much much earlier than we consider normal and strangely they dont report rampant IBS etc.
I agree that the sudden failure to sleep through the night is not necessarily a sign of needing to start solids especialy at around the 4 month mark but taking nearly 50 oz of formula a day and then suddenly waking up starving in the middle of the night might be. That was my point.
On the whole BF issue, i dont think it is that hard to imagine what the WHO are trying to do with the 6 month guideline. As health professionals they would like to see all babies breastfed for as long as possible and that is not a bad thing. They consider however that beginning the weaning process prior to 6 months (when they seem to consider that supply has become established) a potential threat to longterm breastfeeding. Evidence suggests that many babies can make it to 6 months before their dietary needs require the transition to combined milk and solids so they set the benchmark at 6 months. It is not rocket science. Studies coming to light at the time the guidance was issued suggesting babies weaned earlier than 6 months may have suffered harm tailed nicely into their policy as makeweight arguments but were never the primary motiviation for the position.
Further studies are now showing those risks to have been overstated at best (see the BDA position statement) but the WHO guideline remains at 6 months.
So my point was, however inelegantly stated, that where a child is displaying developmental signs of readiness for solids the 6 month rule is more of a concern for breastfed babies as beginning earlier than that might constitute a threat to continued breastfeeding. As a formula feeder it was less of a concern to me.