I'm all for metric/decimal. I get ten kilometres per litre in my car..
Can't wait for decimal time - ten seconds one minute, ten minutes one hour etc.
Seriously, I'm with Kevin, but not because of body units rather the convenience of trade measurements. Horses are in Hands, bricks in courses. and so on. Tradesmen already ignore metric rules which is why Kitchen units are given in millimetres, waist and collar sizes in centimetres; no-one uses decimetres for anything. Metric/decimal was great for the abacus though