"Moe" wrote
I think you better read Armstrong's installation instructions again. It
says "just prior to installation, lay flooring out flat to acclimate to
conditions". It doesn't say a thing about 48 hrs.
http://www.armstrong.com/content2/resam/files/23444.pdf

I should clarify it doesn't say a thing about laying out for 48 hrs, the
key words are "just prior to installation, etc".

The mention of 48 hrs. in the installation instructions is in reference to
climate/temperature.