Hi Jonesy,
Speaking as a mother myself, i can see where your wife is coming from, giving a sweet treat with a meal is the best way to do it. The added fact that one can bolus for it, is fantastic, but would i allow my son treats after every evening meal NO. As well as being unhealthy it is also teaching him bad eating habits. For a treat after an evening meal, my son has an option of yoghurt/fruit/sugar free icelolly ( as he is also Coeliac, sweet puddings, cake rarely happen in our house, and he doesn't like ice cream )and the odd sweet treat is usually reseverved for after Sunday dinner. He does get a bar of chocolate on a Friday night as a treat before youthclub, which i know he'll burn off.
It is hard to say no to a child, after all they are children and we often feel we need to over compensate because of their condition, but we do have to teach them that control is the key point to a healthy future, and that begins now, with a healthy diet.
Then again deny them too much now and they could over compensate when their older, its all to do with balance.
Suzi x