Just to note, though I'm sure it's been noted a few times throughout the topic... many NETs are a waste of money when they only teach 30-50 kids per class, 3 classes, for 40 minutes a week.
I teach 20-30 kids for 40 minutes a day, 3 times a week (sometimes four depending on random schedule changes that are never explained to me). People in similar situations, or people who teach more often than I do, are certainly valuable.
A lot of reactions to this article have been... well, reactionary. NETs can really be a colossal waste of money.