Inconsistent Template Matching - docusignapi

Question

I'm using the CreateEnvelope() method of the SOAP API to upload a document to DocuSign in the Draft status. When I do this and then request a Sender Token to start an Embedded Sending session, I'm immediately prompted to apply a matching template when the DocuSign interface appears.
If I don't start an Embedded Sending session, however, and the user instead logs into the DocuSign console and opens the Draft envelope, they are NOT automatically prompted to apply the matching template. They have to manually press the "Try automatic template matching on all documents" button, at which point the same template that would've been found automatically in the Embeddded Sending session is found. Is there a reason for this discrepancy?
bool retVal = true;
DocuSignService.DocuSignWS.Envelope envelope = new DocuSignService.DocuSignWS.Envelope();
if (credentials == null)
{
error = ErrorCode.NO_CREDENTIALS;
errorMessage = Strings.GetString("STR_DS_NOCREDS");
return false;
}
envelope.Documents = new DocuSignService.DocuSignWS.Document[itemList.Count];
if (credentials != null)
{
int index = 0;
foreach (Document document in itemList)
{
DocuSignService.DocuSignWS.Document doc = new DocuSignService.DocuSignWS.Document();
doc.ID = document.ID.ToString();
doc.Name = document.Name;
//get document bytes
doc.PDFBytes = document.data;
envelope.Documents[index] = doc;
index++;
}
Tab[] tabs = new DocuSignService.DocuSignWS.Tab[0];
envelope.Tabs = tabs;
envelope.Recipients = new Recipient[0];
//send?
envelope.AccountId = credentials.dsaccountid;
envelope.Subject = "Documents are ready for your signature";
envelope.EmailBlurb = "Documents are awaiting your signature.";
envelope.EnableWetSign = false;
DocuSignService.DocuSignWS.EnvelopeStatus envStatus = new DocuSignService.DocuSignWS.EnvelopeStatus();
using (ServiceWrapper client = new ServiceWrapper())
{
client.UserName = credentials.loginemail;
client.Password = credentials.loginpassword;
client.IntegratorKey = "xxx-xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx";
try
{
envStatus = client.CreateEnvelope(envelope);
}
catch (Exception e)
{
ErrorViewerWriter.Write(e);
error = ErrorCode.UPLOADFAILED;
errorMessage = e.Message;
return false;
}
}
}
return retVal;