Have to admit to this myself, chancing pilot cleared to FL190 and wanting to keep a continuous climb...
CS XYZ "approaching FL190"
I observe on radar a/c passing FL153 and without even thinking press the TX switch and say
"CS XYZ you lieing b***ard" (Was in a particularly bad mood that day.)
My Co-ordinator says "you transmited that"
I am just replying no i didn't when...
CS XYZ " my apologies you're quite right now passing FL160"
phew!!!! nothing more said