In regards to the value of asynchronous workflows, in Robert's own words:
When working with the .NET BCL all I/O operations use one of two models, the synchronous model or the asynchronous model. .... In my experience most programmers tend to use synchronous model because of its simplicity and because there are many class in the BCL that only support the synchronous model, but in many case the asynchronous programming model can produce a more responsive and more scalable application.Robert then provides several code samples and quantifies the performance improvements gained through the use of asynchronous workflows.
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