As the title suggests,
When and why would we use RetrieveMultipleRequest over Service.Retrievemultiple?
Can I please get one or two scenarios where one would be more preferable to the other?
My understanding is that RetrieveMultipleRequest is similar to doing a FetchXML query (and can in fact use FetchXML instead of a queryexpression).
Is this the reason? If so, what can you do in a FetchXML query you can't do in a QueryExpression?