As I said above, I merely use CC. This gives the recipients the option of replying to everyone or just to me. Sometimes you'll want everyone to reply to everyone else, but since reply-all is just as easy as reply, I prefer the one that doesn't assume the former.
I don't understand. If I hit reply, then I reply to the person who sent. If I hit reply-all, then I reply to everyone who got the email (barring bcc, of course).
This is unaffected by To or Cc was used.
Did I miss something?
That sounds right for Gmail. Maybe his experience is with another email client.
Either that has not been my experience, or I've lost my mind. Both are possible.