Why get wrapped up overly on whether Jacobson is hoop or a revelation. It has helped many find the correct point to flare and no doubt those people swear by it. For others it is overcomplicating an essentialy basic skill. Neither is wrong. For someone struggling to find their feet it may be enough to give them something to hang their hats on and is worth a try.
I have never come accross Jacobsons technique before but it has some merit in my view. Promoting a constant approach angle all the way to the flare is correct technique as is achieving a consistent point to flare which is what Jacobson is about.
What I would say is that the flare point and technique needs to be as the manufacturer recommends. If not your doing it wrong so know that advice for your type.
The 2 most common errors I see on the line day to day are people shallowing off their approach in the last 100 ft especially the last 50 ft taking them long and flat and initiating the flare too high. Many do not even realise they do it.
Essentialy people lack the confidence to bring the aircraft all the way into the flare point and become ground shy. Encouragement from colleagues is needed alongside discipline, courage and determination from the individual to drive the aircraft into the flare point. If Jacobson helps someone find that point then good for him.