Unfortunately I realize that is true. It’s exactly the reason I stress not to blindly trust me, but to try things for yourself and decide what works for you.
My only hangup with the late addition method is that there needs to be an asterisk because not all brewing waters are created equal. With my home well water, the dark grains in the full mash act as my necessary pH adjustment. if I were to hold these dark grains to the end, I would then need to add acid to the mash for pH purposes. To me, that seems indefensible. Or am I wrong? Did they hold the dark grains out in Dublin? (just kidding)
However, I’ve never tried the late addition so there’s another asterisk. 
I agree. I should ensure I say this works with RO and distilled. It is clear in BBB G Strong uses RO.
He also makes it clear, and Martin has highlighted in other posts, that a small addition of a weak acid and 50 ppm Ca is used in the mash.