The article says that audio alone causes kids to struggle harder with understanding. The whole point of what he is asking is to meet in the middle where kids can understand and get the most out of the media.
Bingo - I have a 3 year old and the effect TV has on them is astonishing... complete trance. We read books every night and she gets really engaged and remembers very specific details weeks later.
As every parent can attest to, there are just times when putting a kid in front of a TV is helpful (airplane rides, when caring for other children, when you need a break etc) so it would be nice to retain some brain activity, or as you say, meet in the middle.
