To answer the original question: DD was 4 months and waking up three times in the night to bf when her pediatrician told us "Either you teach her to sleep through the night NOW, or she will continue to wake up in the night until she is 2 years old". Something about sleeping habits getting solid after the first six months and it being very difficult (if not impossible) to change after that.
She said a four month old baby drinks enough milk at one sitting to last her through the night, and that she wakes up to feed not because of NEED but because of HABIT. Having lived in a predominantly Muslim country for a while, I could understand what she meant: Muslims who fast every day in the month of Ramadan wake up at 2 AM every night, eat loads, then go back to bed to eat or drink nothing until sunset the following day. After Ramadan is over, they STILL wake up at 2 AM with rumbling bellies, although they are not fasting in the daytime anymore. After a couple of nights of waking up, tossing and turning, and going back to sleep without eating, the habit is lost and they sleep through again.
[I know, a baby is not an adult. I am just giving an example of a similar situation in way of explanation.]
Anyway, we stopped night feeds that day. DD would wake up wanting to be fed and we would rock her, kiss her, pat her, hug her, do everything to get her back to sleep without feeding her. We had two tough nights but she slept through the third night and has been sleeping through ever since.
At no point have we "abandoned" her. We were always with her when she cried, but there would be no feeds.
DD is now 18 months old - a very happy, bubbly, cuddly kid who still goes to bed easily and sleeps through the night. I don't regret not having waited for her to sleep through on her own. I am a better mother since I started to sleep well, and she is a happier and more alert baby since she started to sleep well.
Hope that helps those of us who might be considering breaking the night feed happy of their little ones. Not trying to say this is the best way, just posting our experience. If you are happy to not sleep more than a few hours at a time for years, more power to you.