Like the drunk said to the frog, "I'm gonna show you one more time..."
Here is what it is like with a REAL diagram of the forces as they REALLY are Note that the MT thrust passes close to the CG, but misses by a bit, so that the MR thrust makes some moment to help cancel the TR moment. If the TR was directly on the CG, the Main thrust would pass right thru the CG. (I used your diagram cause its better than mine, by a long shot!):
For a High TR, here is what happens:
