This question stems from this question Code documentation how much is too much?
One the answers was to keep your xml documentation in a separate file. I really liked that answer as when I am looking through the code the verbosity of the documentation is annoying, on the other hand that verbosity is usefull when searching for the right method via intellisense or publishing the documentation.
The answer was to use the include tag
/// <include file="Documentation/XML/YourClass.xml" path="//documentation/members[@name='YourClass']/*"/>
There is also a MSDN article about the include tag here.
I figured out how to keep the summary information out, but I do not know and I couldn't find it how to put the method documentation there as well. (which is more important than the class summary itself.