Laminate Flooring - few questions
I am from AZ also, Flagstaff.
If you are going to install over tile it is suggested you back fill the grout joints.
Always use a moisture barrier over and concrete slab. tile or no tile.
Do not attempt to install any wood over the slab just deal with the high are with a modified transition.
While AZ is very dry you can have an reverse effect with moisture this is a type of hydrostatic pressure. The slabs are not as moisture free as you think.
What happens is the heat of the ground surface process chases the moisture to the shade, this shade will happen to be a slab, this slab will have a gravity induced inviroment that will draw moisture from the surrounding area, hence all the moisture in the yard is up under your slab.
You see this effect when you move a rock and find the ground damp under it. Now think about your slab and the wieght of it pushing down, it will draw moisture like a sponge.
If you were to install wood on top of the slab you woul actually draw moisture through the slab and up into your wood.