From all of the reading I have done on floating floors over the internet (diy, thisoldhouse, etc) everything I came across indicated to apply the glue to the "groove" of the wood. However, in the installation manual for the wood I purchased for my floor indicates to apply the glue to the upper edge of the tongue along the whole length of the board? I assume following the manufactures directions is always best - but any thoughts on why the tongue and not groove? What is better?
Amy