Shirley the crew could have at least informed my French colleagues as to what it was they were doing since it was "only" a TA they were reacting to - not waiting until after the (non) event.
I've seen replay upon replay of incidents whereby crews have taken separation into their own hands in the lateral plane (tee hee etc etc) - when given a TA by their little on-board box - often with a resultant actual loss of separation (one particularly nasty incident involving two cargo aircraft coincidentally over France springs to mind).
As livingdead rightly says TCAS doesn't work well on the lateral plane at all - you're offered a very very very distorted picture on the FD thanks to the vagries of airborne radar, moving targets and all that sort of stuff.
I'm sure when the chap / chappess files the incident it'll all come out in the wash
