Quote from Linktrained:
"IF THS is usually " 5 units Plus or Minus 2 units" .... But is seen to be outside this range ... THAT might make a Pilot suspect that something might be WRONG. "
Not having flown the A330, I stand to be corrected, but I think 2 deg NU plus-or-minus 2 deg might be nearer the norm in high altitude cruise. It varies, as you would appreciate, with CG position, weight and speed.
In AF447, the PF's inputs on the sidestick resulted in the THS correctly auto-trimming ultimately to its nose-up trim-stop of about 13 deg NU. This could have been reversed, of course, by sustained forward command on the sidestick, as PJ2 demonstrated in the simulator (see quote by Turbine D, above).