REST API Batch using DependsOnRequest with GETs

Hello:

I've used the Batch in the API (Version: 15.0.6), and I wanted to use the DependsOnRequests feature so I can grab values from other result sets to feed a request, but apparently it doesn't seem to work when you only use just GETs.  For example, in the Batching section, an example is given that has three requests batched together, with the last two requests being linked together via the DependsOnRequests node, but that example contains two POSTs and a GET, rather than all GETs, like what I've tried to do here:

<BatchRequest>
    <Requests>
        <Request>
            <HttpMethod>GET</HttpMethod>
            <Id>1</Id>
            <Uri>example.fake/.../Uri>
        </Request>
        <Request>
            <DependsOnRequests>
                <DependsOnRequest>
                    <Id>1</Id>
                    <IsUrlDependency>true</IsUrlDependency>
                    <SourcePath>Title.Id</SourcePath>
                    <TargetPath>titleId</TargetPath>
                </DependsOnRequest>
            </DependsOnRequests>
            <HttpMethod>GET</HttpMethod>
            <Id>2</Id>
            <Uri>example.fake/.../Uri>
        </Request>
    </Requests>
</BatchRequest>

The result here is that the first request works fine, but the second request gives a PARAMETER_SHOULD_BE_INTEGER error, which looks like the {titleId} placeholder isn't being replaced with the value that is specified in the SourcePath node.  I'm guessing either I'm doing something wrong or that's just how it works and that there's really nothing I can do about it.  Before I trashed this, I wanted to make sure by getting some kind of confirmation here.  Thanks for any help.