There is a somewhaht different perception of carb icing in the US to the UK. I suspect some of that is the difference in temperatures, or rather the difference between ambient and dew point.
But there is also a big difference between a Lycoming and the Continental ice making machines. i've mainly flown behind the ice making machines - Continental and Gypsy. So your technique is largely the one I have used. But I have also had the same sort of comment in the US about the need for cab heat. Or rather the lack of need of carb heat. Given a good gap between ambient and dew point and a Lycoming then probably carb heat is largely not needed.