Don't forget that they were invented long before we had microwaves to quickly reheat our tea.

I'd rather drink it fast enough that it is hot in the pot (yes, it gets stronger, but that's okay) than reheat it in the microwave. That does change the flavor.

I drink loose tea mostly, but we (Moonglow, actually, but she wasn't drinking it) had a Secret Santa box of Yorkshire Gold bags (via a Secret Santa whose initials are "Micca") and I ran out of the loose tea and was a little short on funds so started using the bags in my tea pot. That stuff is so strong that one bag makes a pot full of very stout tea. Now back to the loose tea again. One of my favorites is a very strong Chinese variety called Yunnan. Hard to find around here, though, unless you buy it very expensively in loose bulk at Central Market. I order it by the can from Pearl River in New York City.

SRS