Are there any good MDX training courses that you could recommend? I have found several with varying content scope, from the course outlines, though it is hard to judge based solely on that.

The SSWUG Business Intelligence Conference this April has several sessions related to SSAS and MDX.  The presenter, Craig Utley, has a session "Avoid Slow SSAS Queries: MDX Query Troubleshooting".  Read more at http://www.vconferenceonline.com/shows/spring09/bi/

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