When you meet people you know in Britain, you kiss them on both cheeks. When you meet people you know in America, you hug them. When you travel from one country to the other and get the two types of greetings mixed up, you get funny looks.
In business circles, mixing the greetings generates confusion. In America, British cheek-kissing – especially with a colleague of the opposite sex – can appear to be inappropriate. In Britain, the American bear hug can feel overwhelming and claustrophobic.
Poor Ian! He travels back and forth, and gets it wrong in both directions.