An improvement indeed. Analysis of TCAS events during the last couple of years showed that there were several occasion on which pilots misinterpreted the TCAS command 'ADJUST VERTICAL SPEED' - which always means to REDUCE the vertical speed - and instead gave an input in the complete opposite direction.
E.g. during a 'CLIMB' RA, followed by a 'ADJUST VERTICAL SPEED', some pilots initiated a descent, while just a reduction in vertical speed was asked.
With the new certification and the possibility to use the FD during a TCAS RA the probability for such an event is further reduced.
But that is still no replacement for proper crew training...
Just my 2 cents,
DBate