dongding oolong has a very diverse range of oxidation so does tie guan
yin.

generally autumn and winter dongdings are very lightly oxidised, just
like a baozhong tea or even lighter sometimes.

else lower altitudes and grades of dongdings can also be toasted to
give Tan Pei Oolong tea, which is a lot higher in oxidation.

Tie Guan Yin has a large variety of oxidation, high grades of TGY are
often lesser than mid oxidation, preserving the natural fragrances, a
yellowish brew, nuances that could be lost or overwhelmed by higher
oxidation levels.

i suggest about 4-5 grams of tea leaves to be put into a small gaiwan,
of about 100-150ml, washing the leaves for 2 seconds and draining the
water away, and infuse for the next 15 seconds, and decanting into a
drinking cup. this can be repeated many times extending the steeping
times by 5-10 seconds. dongding is quite mild a tea, using more leave
and shorter brewing time in less water will give a rich flavoursome
brew, with the best fragrance and texture in the second/third brews.

you can brew it in tea pots, but do not infuse for too long. high
mountain tea leaves are very lightly oxidised and tender green. high
temperatures for a few minutes will end up giving you a vegetable
soup, which tastes pretty terrible.

just like good green tea, short infusions of good leave quantity gives
great flavour. but when poorly infused, with high temps for long
periods of time, it becomes so medicinally bitter and the delicate
scents and fragrances are lost.

there are varieties of high mountain oolongs that can be infused in
boiling water and for longer periods of time, i.e. more highly
oxidised teas, slightly mediocre grades. a small 2.5 gram tea bag can
flavour a larger amount of water, without the true quality of a higher
grade