Mark, I think you’re on to something. Most of the discussion surrounding the use of raw TiO2 powder is how it’s mixed and applied… there’s no question it fuses to a ceramic/glass surface when hit with a laser.
Overnight, I also got to thinking about a couple of budget golf courses I’ve played on. The ground in that area is what’s not-so-fondly called "black gumbo" and it “eats” up golf balls like crazy in the summer, with all the cracks that open up. This area used to be great for growing cotton (both my parents lived that experience) but it’s horrible for house foundations and golf courses. The ground “moves” a lot… swelling, shrinking, and cracking with the amount of rain it receives, or doesn’t. In summer, folks have to water their house foundations and better golf courses IIRC water heavily and mix in sand to keep ball-eating cracks from forming. So, keeping it moist and adding filler is starting to make sense to me.
I know some folks are adding PVA glue to the recipe… so “locking it in place” as it dries. Now that it’s starting to make more sense to me, I need to go look more closely at some of those recipes… it shouldn’t be too difficult or expensive to add a few drops of water-soluble PVA glue to the mix.
I’ve also thought about "dry application"… dusting the tile with a light sprinkling of powder, maybe with a make-up brush or nylon powder-bag (… stay with me, guys! 
). Coating the tile with a glue stick, maybe a heat-gun to soften/spread it, and then sprinkle with powder? Maybe a lint roller would leave a light sticky coating on a clean tile… enough to hold the powder in place? I can really see me making a big mess and/or wasting a lot of TiO2 powder with this though… 
Maybe easier, I could keep doing what I’m doing… doing the “bulk application” with alcohol and spray bottle and let it crack… then lightly dust with a makeup brush and shake with my “shake table” to fill the cracks. I’m thinking the less dry dust in the air, the better.
I’ve already picked up a make-up brush and lint roller from DG… getting the usual strange looks for loitering in the “ladies section” while trying to find emory boards, make-up brushes, and/or finger-nail polish (paint for fishing lures). C’mon guys!
– David