I think its a very theoretical way but at least you can effectively get it done after 2/3 times oral instruction. I think its important that they understand you mean it and they see result immediately.
I tried to practice this way seriously and I can see the different. My problem is I sometimes forgot to take action but only repeating oral instruction.
Let's start training them as early as possible, they will get used to it and learn your way!!! I beleive habits and behaviour build up slowly bit by bit and we should correct them before the bad behaviour becomes habits.
Totally agree that kids nowadays are much more difficult to handle and shape them well!!!
Though I know the theoretical way, I dont practice it well!!
For me, I am still learning how to guide and teach CH to follow my instruction within 2/3 times oral request. His major problem is no response no matter he hear or not! And he has been getting habitually not responding especially at home. Its fully our (me/daddy and maid) fault by mis-training - only repeating by shouting without real action.