430ex II question

[wisv1k]

I asked this in another forum but no answers yet and I am a bit puzzled. I recently purchased a 430ex II for my T1i. What I don't understand is why the flash shows 50mm when the lens is at 55mm. The only time they correspond is at 35mm. I understand the crop factor but the hard numbers don't make sense to me. Can anyone explain this? The flash is set for auto sensor size? I just want to be sure the flash is functioning as it should since the first one I bought was returned due to a faulty button. Thanks!