If your baby needed physical contact to sleep and you used a chair then are you saying you slept whilst holding him in the chair? My DD was like this FROM BIRTH. When I held her in bed at hospital I realised how calmer she was when I put a hand on her head. It wasn't a warmth thing either.
My DF slept on a blow up mattress on the floor of the living room for 2 years. It started when I was about 6 months preg to when DD was ready to sleep in her own bed. Oh and for the record, DF and I are as tight as we have ever been. Whadda ya know, DD was never in danger. In fact she was safer because I got to have some sleep. I defy anyone to have maybe 3 hours of very broken sleep a night for around 12 months, look after a pre-schooler with their own issues and maintain sanity.
Finally, I would strongly suggest you don't imply that others risk their babies' lives by co-sleeping. It's highly insulting and offensive. How would you feel if it were stated that you risked your baby's life by RIC'ing?
I'm never quite sure why you enter discussions about co-sleeping given it's something you've never *had* to do to get any sleep or even rest. If you've never done it, how can you have such a strong anti-opinion? DF gets up before me and there's nothing I like more when I wake up to have a snuggle with DD. It's very cute when she grabs my arms, puts it around herself and snuggles into me.