I read the superheating theory too, but I don't think it's really a concern, especially if you are using a timed heating of a measured amount of water. If you'

I read the superheating theory too, but I don't think it's really a concern, especially if you are using a timed heating of a measured amount of water. If you've figured out how long it takes to get to 185F, you aren't going to unexpectedly reach 220F. More generally, I'm not worried about boiling water in the microwave for other purposes, and if it was a problem, I could probably avoid it by throwing a couple marbles in. Definitely there are other ways I can heat water to make tea. I was asking the question in an open-ended manner in case someone had a microwave method that I wasn't aware of. For example, there was an Australian study that got some attention a couple years ago suggesting that one got the best extraction by microwaving with the tea in the water. This dodges the question though of whether the "best extraction" equals the "best cup of tea".