Hi Tilier. Thanks for the thourough analysis.

Having a floating floor was my fear. The weakest part of it would be
the seams. After reading everyone's feedback, I'm guessing I would
have a beautiful finished floor for a year, and then a gridwork of
cracks running through them leaking moisture. Each year it would look
worse until it completely fell to pieces. I guess I'll back off.
Thanks for talking me out of it.

The sand / thinset solution is intriguing. Great analogy with the
booger. I swear I've never done that before, yet I know exactly what
you mean. Half of my intention is to solve the moisture problem, the
other half is to make it look nice and tidy. I'm pretty sure I could
strike a smooth clean surface with my pool trowel. Also, for the latex
"link", someone once told me that the throw-away latex paint that
sells for $2.00 / gallon works great for this as opposed to the $30 /
oz. sold by the good folks at Quickcrete. Any thoughts on this?

Thanks again,
Tom