> I would actually count that as a 4.7kg improvement!

When I quoted 2kg of weight, I meant '2kg of weight', not anything more complex. That's the total change. The exercising twins weigh 2kg less, total, all in all, on average. (If you think you've found a twisty interpretation of quoted figures which is more positive than it looks, please check the fulltext first - that's why I provided it!)