Often, I select bits of an email, to copy and paste elsewhere to check things. Then I hit reply, and wonder why only the currently selected text is there.
mail.app on OS X also does this ( can be turned off i think ) and its always a similar annoyance to me ( select something to copy paste and the reply only has that)
At the very least, when you select text it should allow you to "Reply to Selection" as an option in the reply button (perhaps as default). I leave it to the UI experts to determine what's default and wording/icon changes. This meta-mode shouldn't reuse the reply keybinding either, and use a new one.
This would be far more discoverable and only minor changes to documentation over the current approach.
Often, I select bits of an email, to copy and paste elsewhere to check things. Then I hit reply, and wonder why only the currently selected text is there.
There should be a way to turn this "feature" off.