Please help me to understand:
The ICAO standard phraseology (under the rubric "Cancelling Take-off Clearance") requires the controller to assess the aircraft's state (rolling down the runway or not) and then transmit the state-appropriate message using equivocal terms ('hold', 'position', 'stop' -- which can and play the role of adjectives, verbs and nouns), even though the desired effect (cancelling take-off clearance) is the same, regardless of state.
So, if during the time the controller screams "Cancel take-off", the aircraft starts to move, is the phraseology suddenly non-standard? Does it make a difference? Is the appropriate response suddenly, "Too late, I'm already rolling! See you in H*ll, suckers!"
The horrible US phraseology incorporates the ICAO phraseology for one of the two states, in fact, the state that uses univocal words, and extends them to the rolling state (to which it would be applied anyway); as a result, the phraseology is completely different for take-off than for taxi, and the controller need not vary the wording to account for something that has no effect on the desired outcome. For those at the pointy end, the meaning should be immediately clear, unless, of course, they're completely incompetent, as appears to be the case.
Is there an ambiguity here?
I'm sure there are plenty of examples of non-standard phraseology causing problems, but this isn't one of them.