I have no strong feeling with Green one way or the other, but I agree 100% with your logic. It is the only thing I have "seen" that makes me think he will be a Vol.
Beyond that, the logical arguments for Green to become a Vol are compelling -- stability of staff (new staff will be given at least 3 years); Graham will be his position coach for his entire college career; living and playing during the winter in Tennessee and the South (SEC area) is far more pleasant than living and playing in Michigan and the North (Big "10" area); playing in the "Championship League" SEC as opposed to playing in the largely irrelevant "big 10"; Tennessee offers guaranteed early playing time with a high probability of being the starting RB right off the bat -- that is not the case with Michigan; and while he would have a relatively easy path to the NFL at either school, scouts tend to give extra credit to a player in the SEC who plays weekly against the toughest competition in the country.
If Green is mature enough to use sound logic as the basis for making his decision, the choice becomes easy and he will be a Vol tomorrow afternoon.
mlsoft