Prediction by Gartner on tacit knowledge

I found a great article on ELearn Magazine by Eric Sauve, CEO and Co-Founder, Tomoye Corporation called Communities of Practice: Addressing Workforce Trends Through New Learning Models

Eric notes that

industry analyst firm Gartner estimates that the frequency of non-routine situations requiring tacit knowledge will double between 2006 and 2010. The reality is most organizations' situations change rapidly, making formal training once or twice a year inadequate. Organizations would be well-advised to shift budgets and resources from formal learning settings to informal situations where the majority of learning actually takes place.

The definition of tacit knowledge here is

complex interactions which require that people handle ambiguity and solve
problems based on experience

but how on earth do you measure this? I'd be interested to see the metrics Gartner used to came up with their prediction.

I'm definately all for shifting focus from formal training, which I believe people tend to jump to at the exclusion of all other learning opportunties (maybe because they are more difficult to manage?)

A useful introduction to communities of pratice though...