On having done something yesterday

An Australian correspondent writes to say that he's encountered sentences like I have been to the cinema yesterday which, he says, would be 'completely out in British English'. It seems like a natural development, he adds, but asks: 'isn't this against the "rules" of simplicity, which languages are so keen to comply with? Isn't it more "economical" to use simple structures than complex ones and aren't languages prone to such economy?'

I don't think economy has anything to do with it. Simplic...