Laying out Laminate Floor Diagonally
At least 20% waste, take 50 % longer, no way to block it so it would not move while tapping it together.
If you really want to do a diaganal go with engineered wood flooring, it gets stapled or nailed to the floor so it will not move when installing. It woould look like real wood (because it is) would not look like a plastic floor, can be refinished, does not have a hollow sound when walking on it like laminite does. Will increase the value of the home not take away from it like laminite will.