Here's what I did

I pushed.
Thanks for all the comments in the section. It was not exactly the wide-ranging discussion that Hoy gets on his blog, but I didn't post any fancy screenshots, and let's face it, he has probably five times the readership I do. For good reason.
This is a classic example of my game lately. I realize I need to increase my aggression and no longer settle for a $.68 cash on every MTT I enter. But there's a fine line between aggression and reckless abandon, and I'm having a hard time finding the difference.
The play is justified. It's hard to see how a flop of 9,9,3 helps a player who limps when the blinds are high and then calls your 3xs raise. Unless, of course, he called your raise out of position with K,9. That's a terrible play, in my mind, especially when the guy raising has you covered (what are you beating here exactly), but it's my fault for making the play profitable.
I pushed because I'm not betting 800 into a 3,500-chip pot, and checking does seem pretty namby-pamby, something I'm trying to change.
But I had enough chips even if I give up the hand, and so next time, I may have to take that into account. After all, I probably cost myself $1.23.