I have a package of Harney & Sons "Japanese Sencha Premium Green Tea" bags.
The brewing instructions on the box clearly call for boiled water to be poured into a warmed pot or mug (containing the tea bag) for three minutes.
I woud imagine Sencha would (should?) taste better when brewed using water from the kettle at 170 or so (maybe even in an unwarmed cup?)
What's going on?