Jeff Thorman in his hardwood flooring videos recommends the occasional need to glue a board to the sub-floor. Gaylord hardwood flooring educational videos stress that gluing a board will cause the floor to cup. Who's telling the truth here?

Some acrylic base wood flooring glues need to flash for a little bit of time before positioning boards into the glue may be one reason not to use glue.
If the flooring has not acclimated enough before fastening the boards can expand against several rows that have been laid and could press against the almost immovable glued down boards creating enough pressure that as the unglued boards gain moisture from the air and expand widthwise against the glued boards there may be cupping. It is important that hardwood flooring has a chance to acclimate to the condition of the building so expansion after laying is kept to a minimum.
Some flooring manufacturers recommend glueing boards 5 inches in width and wider, since the fasteners only hold the tongue on one side of the boards.

The hardwood I am installing has acclimated for over a month and checked with a moisture meter.

Ready to lay the flooring?
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