To Treat or not to Treat

Bedtime ritual in our house:
Both of my dear sons are sent to bed at 8pm on weeknights. The older non-diabetic is allowed a glass of milk and sent to brush teeth and get in bed. The youngest son and T1 is asked to test his BS. If he is above the 150 mark we give insulin. If he is between 100 and 150 we check IOB (Insulin On Board - a nice tool when using an Insulin Pump). If there is no insulin on board he is allowed a small glass of water and sent to brush teeth AND go potty before getting into bed. Our T1 ds has a tendency to wet the bed, normally only when his bs is goes above 180 at night but we encourage him to empty his blatter each night regardless. Now then - when his bs is between 70 and 100 with no IOB I struggle with what exactly to do. Lately I have been reducing his basal (again a pump thing) by 40% over a 4 hour period and not giving him any carbs. That has worked out nicely. Most nights when I do this he stays within a few points of his bedtime sugar over the 4 hours and then creeps up just a little after the four hours. I do the same for my dd. So those that are more experienced - what are your thoughts on this attempt at maintaining good sugars?