I'm an occasional tea drinker: as I write I'm sipping a mug of tea, which I'd intended to make without milk but my automatic pilot intervened so I've ended up with my customary brew, without sugar but with milk.
Whenever I think about tea making advice I recall George Orwell's 1946 essay "A Nice Cup of Tea". Orwell was dogmatic about this, as he was about many other matters. He sets down 11 precepts, beginning with an instruction to use only Indian or Ceylonese [Sri Lankan] tea: "China tea has virtues which are not to be despised nowadays — it is economical, and one can drink it without milk — but there is not much stimulation in it. One does not feel wiser, braver or more optimistic after drinking it. Anyone who has used that comforting phrase 'a nice cup of tea' invariably means Indian tea."
If you accept this then you may not disagree with too much more of what he says, though you may not feel comfortable about giving the pot a good shake instead of a stir. (This is reminiscent of the traditional Australian tea-making practice of swinging the boiled billy several times to assist the infusion) .
Orwell didn't for a moment think that tea
His last precept was really a prohibition: no sugar. "I know very well that I am in a minority here. But still, how can you call yourself a true tea lover if you destroy the flavour of your tea by putting sugar in it? It would be equally reasonable to put in pepper or salt. Tea is meant to be bitter, just as beer is meant to be bitter. If you sweeten it, you are no longer tasting the tea, you are merely tasting the sugar; you could make a very similar drink by dissolving sugar in plain hot water."
Whereas for Orwell tea making was a ritual, for me it's a routine, made easier by the availability of tea bags, (though I sometimes make a pot of tea using leaf tea). I've googled to see what others have said about the art (or science, or call it what you will). Here's one site which lays down a different version of Orwell's precepts (it approves of Chinese teas) yet in similar fashion to him (it prescribes 8 steps) Despite this it is open minded enough to include a number of links to "bad advice from other people" (including Douglas Adams and Orwell).
As well as reporting the bad news about adding milk to tea, The Times, in another article and the BBC try to reassure the tea-drinking public by putting the German study into some sort of perspective. They quote a British cardiac nurse: "It is difficult to say from this small study the impact of adding a drop of milk to your tea can make. The tea break is a great British tradition which provides time to relax with a cuppa in hand. Leaving milk out of your tea is far less likely to help protect your heart health than other measures, such as taking regular exercise, avoiding smoking and eating a healthy balanced diet."
I'll bear this in mind as I try to turn off my automatic pilot and move to a black (Indian/Sri Lankan/Australian) tea drinking regimen. I'm not sure however whether I'll be able to stop using tea bags.