Quote:"Distortion can cause problems in any speaker because the distortion components can be passed by a crossover and end up in a high frequency driver not designed to handle large amounts of power."

Answer:According to what you say, if you were to send to the prepro/amp a bad recording of a song (containing distortion), when this distorted sound would go to the speakers, the distortion contained in the recording would go to the tweeter, overload it with unduly large amounts of power, and put the tweeter in danger of overheating.

If you'd like to check if distortion damages tweeters, get this file:Thomas Edison - Great Speeches - 1887, First Gramophone Recording Ever.mp3
and play it on your system. The sound is very distorted so it should make a very good test.

I think speakers don't know and don't care if a signal is distorted or not. They just reproduce what is sent to them, no more, no less.
In fact, you can be certain that signals without any distortion don't exist.

Sending too much power to a speaker can damage it; distortion does not damage speakers, it only muddies the sound.

If you'd like to check if distortion damages tweeters, get this file:Thomas Edison - Great Speeches - 1887, First Gramophone Recording Ever.mp3
and play it on your system. The sound is very distorted so it should make a very good test.