After a while I realised that there was always a reason why DS wasn't sleeping well. Mostly I couldn't figure out what the reasons were till after the fact (if ever), but it helped me to resign myslef (like babymama ). Every now and then the stars align with jupiter and hey presto, he sleeps! And he has been heaps better in the past 6 monhts or so, except if he's sick, or has a nightmare, or overtired, or.....
A lot of parents crow about what a great sleeper their baby is. Well my son is a crap sleeper, but he's pretty brilliant in just about every other way