I'm telling you, fuck the dot. At 400, I'm on the irons.
But, with low brightness, knowing your drop, and understanding the center of dot is all that counts and you can do it.
I am going to try using the Matech as well. It won't matter if I use dot or irons, almost 100% of the technique is the same.
When I despair, I remember that all through history the ways of truth and love have always won. There have been tyrants, and murderers, and for a time they can seem invincible, but in the end they always fall. Think of it--always.