[bbartlog]

Assuming that ... player r's skills are equal to the skills of the field, or are superior, we would ordinarily expect the following to be true at the start of the tournament: F_r >= Z/n

I don't think this is true (and that has a lot to do with why I don't play tournaments, generally). Because the tournament payout schedule is quite top-heavy, you need to be on a par with the best of the field in order to have positive expectation. Even if 80% of the field is dead money and you're around the 90% mark in overall skill, you might have negative expectation - though this does depend on just how great an advantage the top players have over you.

However, I don't think this actually affects your other observations.