I posted the following in the Soils forum, but I suspect Al might see it more readily in here. Sorry for the double-post.

I generally like (perhaps undeservedly) to think of myself as a relatively intelligent person. Nonetheless, understanding the process of creating the gritty mix has been a challenge. I've read through the entire latest container soil & water retention thread and several of its cousins. Questions remain, so I'm hoping Al or one of his devotees will help me out.
My problem seems to centre on the screening. Each of the ingredients must be screened twice, correct, so that there's no "dust" and each particle is between â and 1 / 4 of an inch?

For example, the pine bark: Initially, screen it so that there's no "fluff" that is smaller than â of an inch. Then, of what does not fall through the screen, re-screen to remove anything larger than 1/ 4 of an inch.

Then, for the Gran-I-Grit, do you rinse it first, and then screen (that seems like it would be more difficult)? Or, if you get #2-size, is screening required? Again, the size of the particles should be between â and 1 / 4 of an inch, so you'd want two screenings.

Likewise for the Turface?

It has likely been addressed several times, but there are new members joining all the time, and people make have thought of something else since the last time it was asked, but, what do you do with all of the stuff you discard?

Thanks in advance for helping.
(Also, sorry, but the one-fourth symbol doesn't display correctly for me, so I added a couple of spaces.)