just fwiw, i looked at http://www.squeaksource.com/OCompletion/ and there was a paper about ocompletion mentioned, but the access to this paper was forbidden - at least for me. but at http://users.dcc.uchile.cl/~rrobbes/p/JASE-completion.pdf there is a paper about ocompletion by the same author that explains ocompletion and with that paper ocompletion is easily understandable.
werner
I'm currently going through��http://users.dcc.uchile.cl/~rrobbes/p/ASE2008-completion.pdf��and��http://link.springer.com/article/10.1007/s10515-010-0064-x��(dunno if there's non-paywalled link)��to get better idea of how it works... and I can already see why there's limited progress :)