Which Is what a few including myself have been saying:
http://www.pprune.org/8824575-post2010.html
Quoted below:
It certainly didn't help 2 very respectable pilots on D-AXLA A320-232 over Perpignan when THS stayed nose up, with the combination of the AOA sensors freezing and normal law dropping out they were unable to save it with the above aforementioned method (stick hard forward). After reading the report, i was worried by the lack of notification to the pilots, in that moment id expect 'USE MAN PITCH TRIM' to be slapping me round the face. This warning in that instance was possibly the most understated warning.
Why not use a clear indication:
Warning - Normal law FAIL, Law STATUS NOW Alternate/Direct etc
Cause - AOA/ADIR mismatch(or the like)
Result - USE MAN PITCH TRIM(?(perhaps added flashing audible warning if stick forward/backward exceeds Xseconds)) or AUTO PITCH TRIM DISABLED!
(In the tragic Perpignan instance above i believe the PITCH TRIM warning dropped off the display shortly after changing flight law.) i stand to be corrected. Which then left the guessing game of 'what did the AP change we haven't worked out yet'.