There's an option missing in Q2 that I suspect will skew your results greatly when it comes to the crowd here: booking through a luxury travel agent (e.g., one with Virtuoso, Four Seasons Preferred Partner, Ritz-Carlton STARS affiliations, etc...), or online through a luxury travel network like American Express Fine Hotels & Resorts.

I -- and I suspect many others -- book luxury hotels primarily through these channels. Sometimes I'll choose hotels because of their affiliations with these networks (as booking through them gives you additional perks, e.g. free breakfast, F&B credits, upgrades, etc...).

Not really. I don't follow hotel awards much, so I often won't find out a hotel has won an award until I've already booked...or sometimes until I arrive.

BTW, cool thesis topic