andy2000,
it's nonsense to think that when we are in photofocus our brain produces delta waves. You could be in photofocus and producing beta, alfa, theta or delta (delta and theta are less likely since delta usually happens only when in 4th stage of sleep and theta when in hypnagogic state of sleep, however you can be in theta and wide awake at the same time ... have you ever practiced meditation? Heck, you could also be in delta and wide awake ... but that has another name ... OOBE ... 
).
Well, the point is that just seeing a "blip" page and turning pages while chanting (relax, relax, relax) won't slow down your brainwaves from beta to delta, I am completely sure of that fact. Another matter is that, before "photofocusing" you have to relax, this is some kind of meditation, and it's used to slow down your brainwaves.
In summary, photofocus doesn't slow down your brainwaves. However, in order for photofocus to be useful you have to slow them down, hence the "preparation" step.
Anyway, I very, very, very much doubt anyone can be in delta and turning pages at the same time, simply because of the reason that conscious or not, when in delta you are not able to move ... ever heard about "sleep paralysis"? Well, then that would be "conscious delta", hence the paralysis. I don't wanna go too deep into these topics. If anyone want me to go deeper, say so and I'd be glad to explain it.
Finally, I think that the ideal state would be to go to theta and then photoread in theta state. This is way too difficult, but with practice it becomes possible.
