We started off by rocking Aneta and then holding her - she sometimes managed to sleep 2 hours while being held. It was the worse thing we got her used to , it was hot , she was " stuck " to us and sweaty , my arm lost feeling in it ( hehe ).. and nothing else could be done because if i was holding her sleeping i couldnt move.
It took us awhile to get to where we are now.. ( we rock her to sleep and then put her in her cot ).... i wish i had done this from the start - i figure she wakes when she's had enough
IMO each baby is different and its hard to say each one needs 3 hours - dont know how they come up with these magic numbers