Does an HTTP 400 response get captured in SVCTrace?

Question

When reviewing IIS logs I see some HTTP 400 responses. To diagnose the problem, I have enabled SVCTrace via the following configuration....

<system.diagnostics>
    <sources>
        <source name="System.ServiceModel.MessageLogging" switchValue="Warning, ActivityTracing">
            <listeners>
                <add type="System.Diagnostics.DefaultTraceListener" name="Default">
                    <filter type="" />
                </add>
                <add name="ServiceModelMessageLoggingListener">
                    <filter type="" />
                </add>
            </listeners>
        </source>
        <source name="System.ServiceModel" switchValue="Warning, ActivityTracing"
         propagateActivity="true">
            <listeners>
                <add type="System.Diagnostics.DefaultTraceListener" name="Default">
                    <filter type="" />
                </add>
                <add name="ServiceModelTraceListener">
                    <filter type="" />
                </add>
            </listeners>
        </source>
    </sources>
    <sharedListeners>
        <add initializeData="C:\temp\messages.svclog"
         type="System.Diagnostics.XmlWriterTraceListener, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
         name="ServiceModelMessageLoggingListener" traceOutputOptions="Timestamp">
            <filter type="" />
        </add>
        <add initializeData="C:\temp\tracelog.svclog"
         type="System.Diagnostics.XmlWriterTraceListener, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
         name="ServiceModelTraceListener" traceOutputOptions="Timestamp">
            <filter type="" />
        </add>
    </sharedListeners>
</system.diagnostics>

While IIS continues to receive HTTP 400 responses, these do not show in the SVCTrace file. I assume this is because a HTTP 400 means bad request, and therefore a bad request never made to WCF to be included in a trace file. Is this an incorrect assumption?