@Chip Bennett - Hmm so in the end, it looks like this is a no brainer and it is perfectly acceptable for someone who has purchased the theme to send it to me to perform edits and then ship it back.

@David - I bet most theme authors feel the same way. Anytime that theme is sent over to someone else, you end up with that thought in the back of your head wondering if they have redistributed it or if they deleted it or if they are saving it for themselves. I can see how it could be unnerving.

So in the end, looks like what this boils down to is the moral or ethical awareness of the person making the edit?