How warmly should a baby be dressed?

I found this long thread on a forum for expats in Germany - it seems that the English find that the Germans put too much clothes on their kids, and the Germans find the English don't put enough.

Extracts:

When my daughter was born (31 years ago) I learned from the midwife in the hospital that babies always have cold hands and feet. Check temperature on their back - if the body is warm, the baby is fine. 

and

I had my daughter last month and my Dr told me she should wear a hat 24/7 until summer 2010!! My Mum almost fell off her chair when they told me. The Dr said unless I would wear a bikini outside, the baby must be in a hat. My boyfriend is Engish too, but he puts so much faith in professionals that we arged about this a lot. Suffice to say, the baby has a hat on outside when it's cold or a bit of a breeze, and hardly at all indoors! When I had her, the hospital was super hot,and they dressed her in: a vest, cardigan, sleepsuit, sleeping bag and hat and then put her in a bed with a duvet on top! 

 ... huh, so it's not just German old wive's tales versus English old wive's tales ... it's German doctors versus English doctors. That's harder to dismiss, they can't both be right; or maybe it depends of the child's age ...

Anyway, there's also an interesting thread on Yahoo answers, where pretty much everybody is saying that "you need to keep the baby warm or he'll catch a cold" is an old wive's tale:

A cold floor does not lead to a person getting a cold. The cold and flu are caused by viruses. Strep throat is caused by streptococcus, a type of bacteria, etc. I find myself saying this to my in-laws 2-3 times a week. They say that I should put socks on my LG when I walk her on the kitchen floor or she will catch a cold. They still haven't wrapped their minds around the fact that I am a microbiologist and know what I'm talking about. Please, stop this erroneous thinking and let your family know just what causes colds. There may be germs on the floor that could make your BG sick, most likely not, though. I prefer for my LO to be exposed to these germs and let her immune system deal with them. Of course, if the temperature of the floor is uncomfortable to you it will probably be uncomfortable for your LO, so just use your better judgment.