National Identity Crisis part II
Oh my, she replied!

That's not quite what I meant! Your normal English is practically perfect! I mean your posh english such as old bean and things like that y'know? Oh if you watch jeeves and wooster then you can be absolutely spot on! Best show ever.

Aside from the 'practically perfect' (in every way)...

I think Penni would be a little offended that a sixteen-year-old (British) girl is impugning her expertise on, um, 'posh English'.
I think I'm about to reply with and if you read P. G. Wodehouse you can be even better there's more to public schoolboy-speak than Wodehouse. And my beta is the bloody expert.

I'm starting to feel patronised. By a sixteen year-old. Now I feel old...