MTV requires the user to provide the access token for RHV but that's not always necessary - it requires pasting/uploading the token from RHVM while the customer may have everything on internal networks where the risk of a man-in-the-middle is insignificant. 

the backend side is covered by https://issues.redhat.com/browse/MTV-373

this won't work in 2.4.0 for warm migration (that still uses CDI)