I have to agree with Samantha. Many people told me to start giving my son solids early on too, but I waited for the ped to give the ok. He didn't give the go ahead until he was 4 months.
Everyone has their own experiences and everyone who has raised kids thinks what they did is the best and only way. Old school parents started giving their kids cereal as early as 2 weeks, and the fact is a baby's stomach can't handle solids until they are much older. Their stomachs actually have to work harder to digest it. Many mothers give their infants cereal in their bottles at night so they sleep better. Whose needs are being met there?
Yes, single grain cereals may not seem like they have enough nutrition or as much as others, but if you consider a little baby needs simple things to digest. You said in another post that you suspected your LO had reflux. Possibly the complex diet that he was eating was the cause?
To each his/her own, but I'm glad I waited until I had the ped ok, and I still am very careful not to introduce more than one food a day.