The maxRequestLength attribute applies to the web application receiving the request, not the client calling it, so it should make no difference whether you use the CRM web application or a command line tool.
However, when you access the CRM web services directly, the maxRequestLength attribute that applies is under the <location path="MSCRMServices"> element in the CRM web.config. This differs from the maxRequestLength attribute directly under <configuration><system.web> that affects access via the CRM web application
Microsoft CRM MVP -
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