Re: Forgiving the charming villains

Emma shows herself to still be rather naive, and inclined to have her head turned by flattery. She is, however, a very straightforward person, one of her endearing traits, even when she's trying to be cunning and help other people's love affairs along, and probably literally cannot see that some people tell lies and flatter to a purpose. All she sees is that Frank is 'kind' to say such nice things about her.
I think Austen chose the name 'Frank' with deliberate irony because he is anything but frank; he is sly, calculating and enjoys being one up by making fools of others. The letter is carefully calculated and weighted to make those who read it think well of him, because it is important to Frank that people think well of him. He's a conman, and in the modern era one could quite easily picture him getting little old ladies to part with their hard-earned savings which they trust to the 'charming young man' who vanishes with the cash without investing it/arranging a holiday/fixing the roof/etc etc