You are completely correct Northbeach.
Incidentally, I have an old videotape 'building and flying the 727 and 747' which covers a lot of the test program on these two superb Aircraft.
Some of the highlights I remember from the documentary were the high speed testing of the 747 up to .99 Mach and the 727 a mere .96 !
Each Aircraft was found to be vice free in that part of the flight envelope. Just as interesting was the slow speed testing of the 727, which, even with it's T Tail had a very benign, straight ahead nose drop at full stall.
It says a lot for the Boeing aerodynamic engineering department.