Well, I will say that this drastic action was prompted by various recurrences of algae, damping off fungus, and slime mold in my media. Another part of it was that I need some way to keep algae at bay long enough for some seeds to sprout (thanks to SDCPs for the great SASE, and for half of my plants for that matter!) I've had some seeds in a previous batch of media for less than 3 weeks and they're already completely smothered with algae; I fear they won't sprout.
Being that I live in NYC, I don't have great access to ideal media. Even at dedicated garden centers (not just Lowes, Home Depot, etc.) the only brand of peat I can find that isn't Miracle Gro is Hoffman. And it certainly wouldn't be cost effective to order gallon bags of media from online nurseries and pay for shipping every time I want to repot my plants. As far as sand goes, all I can get is Mosser Lee brand desert sand; no silica sand or pool filter sand to be found. Again with the Brooklyn apartment thing: I do have access to play sand, but no room to store a 50 lb bag of the stuff!
Having done this sterilization and repotted many of my plants over the weekend, I must say that 72 hours in I haven't noticed any ill effects on the plants outside of the normal transplant shock.
For the purposes of the scientific aspects of this, I will keep you all posted on how my plants react to this media over the coming weeks and months. I will also get better about top watering my plants to supplement the tray method.
Thanks for all the comments! This is a great discussion.