> Detecting artificial typing patterns is a little more tricky, but also feasible.

Keystroke dynamics can detect artificial typing patterns (copying another source by typing it out manually). If a student has to go way out of their way to make their behavior appear authentic then it's decreasing advantage of cheating and less students will do it.

If the student is integrating answers from multiple AI responses then maybe that's a good thing for them to be learning and the assessment should allow it.