SAW THIS ON A PAGE HERE:

" There are other older subfloor systems one may encounter and not used anymore. They include:

• 1&1/8" T&G plywood subfloor installed at 90 degrees to 4"x 6" beams spaced 4 feet OC.
• 1&1/2" x 5" T&G solid fir deck boards installed at 90 degrees to 4" x 6" beams spaced 4'00" OC.
• 1x8 solid fir/pine boards installed at 90 degrees to joists spaced 16" OC.
• 1" RED-X T&G particle board subfloor installed at 90 degrees to joists spaced 2'00" OC.
• 3/4" or 5/8" particle board found mostly today in modular and mobile homes.

Older subfloors shown above should not be removed [/u]but overlaid with 1/2" CDX plywood that is well stapled (2" around perimeter and 6" OC) or glued and nailed/screwed. In all cases, subfloors and underlayments are to be flat to within a 3/16" tolerance in an 8-10 foot radius. "

I NOTICED" SHOULD NOT BE REMOVED." WOULD THIS APPLY TO ANY KIND OF FLOORING (HARD OR LAMINATE) IF THE SUB IS PARTICLE?

I believe that that post refers not to suitability for the installation of new floor, but to the fact that the subfloor system is an integral part of house construction and does more that act as a platform for your feet. In some types of construction, removal of the subfloor system can "bring the house down" so to speak.