Spending time and resources to produce training materials for an unresponsive prospective user community will actually impede the adoption and long-term success of your knowledge base.
Wiki contributions are down or stagnant. You recognize an abundance of Do It All, Leech, Wikiphobia, and possibly ContributorForHire people anti-patterns. People complain that it's too difficult to get their ideas into the shared knowledge base. You (or your established IT infrastructure) responds by addressing their apparent demands for more training, simpler examples, and more technical documentation.
resources are spent making training pages, duplicating or simplifying application documentation, and making walkthrough videos or presentations (especially in 3rd party tools rather than the wiki itself)
users attend training sessions, but this does not translate to contributions
users don't even attend training sessions but complain that the application is 'non-intuitive' or 'complicated'
despite training, users panic when asked to add an attachment or comment to an ongoing discussion, and revert to email / fax / smoke-signals
it's too early in the adoption process for widespread training
training addresses technical questions of interface and application (the How), but does not demonstrate philosophical differences or encourage cultural change (the Why)
armed with temporary and unmotivated technical knowledge, users will fail to practise
eventually, users will lose interest and conclude the system is not useful for them or does not 'work' in their local 'culture'
some IT solutions are about technical training rather than 'teaching'. 'learning' happens when the student has the triad of motivation , information , practice . You are lacking motivation and perhaps practice . These can't be mandated easily, but rather encouraged.
Use peer tutoring, encourage (wiki Champions
or other adoption patterns to demonstrate utility and encourage use.
Encourage resource spending on training in response to user demand only, not as a means to promote usage.
Consider targetting 'philosophy' campaigns directed at problematic trend-setters rather than technical training