[jsr]

Wow, for people who have never run this setup, or a similar one, you're all very undeniably correct in your opinions.
Some info on my truggy/setup/track:

TTR ST-1
Geared for 35mph (right now, need to pick up other pinions)
Weight w/o batts ~7lbs (complete with BL setup, wheels, tires, etc.)
Batts - don't recall the brand, but each pack is rated for 90A and I run 2 packs in parallel for 180A constant discharge capability
Fans - fans are installed directly atop both the ESC and motor. They keep both quite cool. They will thermal shutdown if the fan is not used. The fans do wonders for this setup.
Track - hard packed dirt, very tight turns with many jumps (mostly small, some quite big), front and back straights that are long enough to allow about 2sec at full throttle.
Usage - I DO NOT RACE. I go to the track for fun. I don't attend during the race days as it gets quite packed. Everyone at the track is just there to run and have fun. No one during those times are very good drivers. On the straight, the BL acceleration keeps up with the nitros. Only an 8ight 2.0 pulled on me on the straights. I can out-jump him as the track is tight and doesn't have much room to build up speed (and thus rpms) for a nitro. Full throttle and full brake doesn't work well on this track. The light dusting of dirt atop the hard pack often makes you slide (although I've never tried holeshots).

If you race, I'm sure your temps will run higher. The A-Mains are usually longer than the 15 minutes that I typically run. Also, considering my track has many tight corners, full throttle is rare. It's a burst of throttle here and there and part throttle through many portions of the track.

The OP asked whether 3s can be done and everyone just follows suit of the old adage of "no way in hell", regardless of what experience, or lack thereof, they have with a 3s setup. I'm simply speaking from experience that YES, it can be done and can be done without everything exploding destroying half the planet. I already stated in my first post that it is not ideal, but it can be done without worries. If that bursts your bubble that 3s is the end of world in a truggy, sorry. Fact doesn't always follow theory.
And also, friends that run Medusas run hotter motor temps than I do. I ran geared for 40mph during bashing and they get higher temps. Don't ask me why. Their motors are "supposedly" more efficient than mine, we're all geared for about 40mph, and they typically run hotter (everyone on 4s). And at bashing, we're all full throttle.