(Paraphrasing)
1. MH would have liked Luke to turn to the darkside temporarily.
2. MH was surprised when GL tried to top "Luke, I am your father" with "Leia is my sister." MH made a comment about Luke pursuing the princess only to finally discover Leia ends up being his sister was disturbing. When MH asked GL whether this was a joke, GL replied that GL always envisioned Luke and Leia being siblings.
Yeah right!
Kevin