No doubt the aircraft knew it was you, and that it ought to behave! Anyhow, I'm glad your comprehensive flight test programme went so well!!!
Now, you said: .
Autolanding depends on electronics, not the piece of metal.
The aircraft wasn't designed to autoland, because when most of the designing was done, autolanding wasn't part of the scenery...
The reliance upon trim bias makes up for an autoflight system that can't cope with the auto-go-around without biasing the trim beforehand, as it's not capable of controlling the aircraft in pitch - it runs out of authority. No, this is not true for all WaB conditions, of course, but is a decent rule of thumb. The electronics will only change the flight path as far as the bits they're controlling will allow them to, and the hydraulics and other bits on the 737 can't cope as well as they're Toulousean colleagues can.
If you want to try disabling the trim system, in some way the FCCs and other bits can't sense, and then autolanding it, it will probably work. But then, try an auto-go-around, and you'll get close to stalling it, at precisely which point, the APs will disconnect...