Fluttershy Wears Glasses

Sort of Sequel to Rainbow Dash Dies An Awesome Death, So Rainbow Dash wants to train Scootaloo how to fly but has to inform her of something that she thought was odd.

A sort of Sequel to Rainbow Dash Dies An Awesome Death.

Rainbow Dash decides to take Scootaloo training but has something she wants to share about Fluttershy.
Why is it so important for her to tell her story and why does Scootaloo not want to hear it?
Also it contains a surprise ending.