It is still encouraging a head set, and a headset at all does not facilitate any kind of collection. By riding and creating a headset--it doesn't matter if you force or 'encourage'--you are riding the horse from back to front.
The article hits far from the true 'collection' mark, because if you take a look at the horse they 'fixed', it is FAR behind the vertical, and broken at the ... third, fourth, maybe even FIFTH vertebra. I know the horse is in a 'long and low headset', but that doesn't excuse his neck being broken in half almost and his head that far behind the vertical.
It seems to me that the MH teaches the horse to escape bit pressure. They will be TOO soft in the face, always tucking their nose away from the bit to escape pressure. The horse will never accept contact, because the way this system works is to release all pressure when the horse tucks his nose.
Not really any different then draw reins or any kind of head-setting device.