Okay – picture the situation. You’re sat in a bar. In through the door swims mega-Olympian Michael Phelps (he never walks anywhere). Emboldened by liquor, you shout “Oi! Phelpsy”. He doggypaddles over and eyes you up suspiciously. “Schwimming… it’s eashy”, you slur. Phelps doesn’t reply. “I bet you fifty quid I could shwim fashter than you!” you continue. Phelps narrows his eyes and fixes you with a steely glare. “I’ll meet you down at the schwimming pool, at 9am tomorrow!” you cry, and fall off your stool…