Thanks for your response. I think it's a matter of semantics in the special case of starting with the first message in an "oldest to newest sort." For example, deleting the oldest message in that sorted list moves the cursor to the next newest message (from my perspective), which _in this case_ can also be considered the next oldest (remaining) message (from your perspective).
Try the same thing - sort in either direction - and delete a message in a position
other than top or bottom. No matter how the mail is sorted, the next newest (by date/time) message will always become the "current e-mail message" after a deletion.
There are times when I want to leave an e-mail in the inbox for a while before I decide whether to reply, delete or otherwise act on it. As a result, I'll sometimes start acting on e-mail in the middle of the messages list. The deletion of a mail message using Mac e-mail always moves the "current message" indicator to the next newest (by date/time) e-mail, which is contrary to my previously primary e-mail clients.
If my e-mail is the only one that behaves this way, perhaps it has something to do with my mail source?
I don't want to make a big deal out of this, because it's a behavior I can get use to. I just have to believe that this is a configurable behavior.