While it was full of flavor, it was also full of problems. Check out SKR's rant why it was switched to Darkvision here: http://www.seankreynolds.com/rpgfiles/rants/infravision.html
I wish more D+D developers published rants like these.
Well that's the first time I've read that article. Many of the problems he identifies, especially those with illusions and invisibility, are clearly dealt with in AD&D. On top of that, visible light is just a form of radiation. In terms of science, you CAN make something invisible to the infra-read spectrum because it's also just radiation, but radiating at a lower frequency. In fact I recall reading that scientists have already made things invisible to the infra-red in the lab.
In addition, I think his use of science isn't justified for D&D. You would need to have an eye over 1m in diameter to see into the infra-red. So clearly, infravision is some sort of semi-magical or supernatural attribute. As such, it doesn't have to conform exactly the laws of science. Perhaps some new form of advanced biology that science hasn't discovered could allow for smaller eyes, but based on what we know, it's just not possible anyway.
I really don't see how anything he pointed out creates a problem during the game. I always found heat sources to be very easy to describe. After all, we have all seen the predator movies
