
I've seen it recommended quite a few times - it seems quite popular over in the US (I go on a few US boards), and if the reports from the owners recommended it is anything to go by it works very well. Personally I don't use it - any issues I've had with my own dogs have been my fault for no training the necessary behaviour - but I do use elements of it.
For example, if we go to the park; the dogs must wait on command in the car, boot door open, till I say "go". Then they must sit at the gate to the park until I open it. It took a few goes, but now they always sit the second I ask - basically the same as the full NILIF program; they want to run in the park, they sit first. Anytime I decide to implement something like this it takes a few goes but it works - and I've noticed their behaviour generally imrpoves, getting a little more responsive with time. The latest one is the front door - my dobe likes to bolt if there's a cat (and owning 4, there often is!), so now both dogs have to wait and sit while I go out first, to check for small furry lunch-like items :) works a treat, they are better behaved generally leaving the house now. So going by my experiences, and the reports I've read in the past from owners who've used the full program, it's worth a go - and you can do it without indulging in any of that pack theory malarky. Probably the best thing about it (and why it's so effective, I believe) is that it encourage consistency on the part of the owner in all aspects of the dog's life, and that alone can work wonders IMO!