As Dave Snowden, points out in this rather old article Managing for Serendipity or why we should lay off “best practice” in KM, they come at a severe cost.
... The common knowledge management focus on best practice is in effect contrary to natural practice; an attempt to impose an idealistic structured process onto the natural activity of learning and knowledge transfer through a focus on efficiency at the cost of effectiveness.If you are new to KM and have not read this article then can I suggest you do :-)