It wasn't "minimal prep"!

Read the page and it is *explicit* that she had been in Scotts mind waiting for him to make a move and immediatly hopped into his mind unnoticed, exactly like computer virus, getting to work on laying the field in her favor - all while he was blithly lecturing scott.
We know she's good enough to do this and we know exactly how she did it. You seem to be implying Xavier should be 101% infallible & omniscient....


"I was waiting inside.... you caught me like a virus... I've been Working away ever since."