Thanks for the definitions. *He used the wrong word, so stop being a
smartass and learn something.

I wasnt being a smartass. It seemed he was suggesting that I install a
3rd layer. I already have a subfloor. He agreed with the other poster
that I should install my 5/8 across the joists, and then suggested I
install a 1/4 inch on top of that. Nobody suggested taking out the 1/2
inch subfloor, which is good because I have no intention of doing so.
But I certainly dont need 3 layers.


"Screws are just plain out of the question"...? *Why?

Because after reading about the pros and cons I decided I'm not using
screws. I might shoot one in here and there
if necessary.

*It's a superior
installation, doesn't cost a hell of a lot more, and unless you're
doing an entire house won't take all that much more time. *Even if you
are doing a whole house, the superior installation is worth the time
and money. *Rent an autofeed screwgun if you're worried about the
time.

If you are going to use nails, you should know what nails do, and how
they are supposed to work. *Underlayment nails, and roofing nails, are
designed to penetrate completely through the wood sheathing. *They
hold much better that way and are far less likely to back out over
time.

I have read the exact opposite. They should not penetrate the
subfloor. That was posted above and I have read it in other places. I
have also read the opposite, but since nails penetrating the subfloor
will splinter (or chip) the bottom and reduce holding power it seems
wise to me not to penetrate it completely if possible. I may not have
a choice though, if I use 5/8 plywood and nails.