I have another update: I spent my first full night of sleep last night. I didn't put any bedding on my mattress, just a single sheet that I wrapped around myself and slept on... all night. Wow did I need that sleep.
I gathered up the courage to face my biggest fear: that the box spring was a veritable bed bugs nest with crawling bugs all over the inside -- which is what caused my biggest fear of sleeping just above it. I took a flashlight and ran through the box spring with increasing confidence, never finding anything that I could identify as living, clearly not a bugs nest. I put some double sided tape along the bottom of the box spring, not to prevent them from getting around but as a test to see if there are any left. I'll check in the morning for any stuck on the tape.
Knowing that the box spring is not in fact full of bedbugs will allow me to sleep a little more soundly tonight. Another source of fear was that the items that I had stored under the bed (seasonal clothing in a box, and zipped up cases with old stuff) was where they were hiding. I cleared everything out and threw out that clothing that I will never wear again. I vacuumed under the bed and washed the floors. There's not a single box nor dust bunny left.
I also moved my Roomba to the bedroom where it can now roam the entire room -- including under the bed -- unhindered. A multi-daily vacuum of the bedroom is now only a button press away.
I'm not ready to declare victory on these bed bugs but the initial pest spray along with the deep cleaning and the lack of any bug sightings has given me confidence to declare that I am winning. A second spray in two weeks could very well finish them off if there are any remnants or unhatched eggs.
Even if I don't see any bedbugs, I'm going to get some of that d-earth and spread it around obvious places under the box spring and in crevices along walls and electrical outlet plates. I'm also getting a bedbug grade box spring sealed cover so they have no place to hide if they do come back.
In the meantime, I'm still living out of plastic bags but I think that within a few days of the second spray, if I see no bugs, I'll begin to put clothing back in the closet.
Bed bugs were largely defeated in the 1950's by potent chemical controls but I think that their demise will come at the hands of the Internet this time around. Information is power, and in that us humans have a clear advantage. We know that they follow your CO2 and body heat, we know how to identify the telltale signs of blood spots and a sweet smell in cases of larger infestations. We know that heat kills them and how they spread. It's only a matter of time before artificial CO2 and heat emitting bed bug traps that can lure, then zap these pests becomes accurate and successful enough that bed bugs will become a thing of the past. Hotel chains can spend millions dealing with bed bugs, so a lot of power and money as well as motivation is there for a solution to become available.