@teaformeplease Nice comments! I, agree. That said, I think that
@Bok simply got a little ahead of
@Guy Juan and this led to frustrations on both sides.
I would suggest that
camellia sinensis v. sinensis vs.
camellia sinensis v. assamica is the same sort of difference as that between
arabica and
rustica. The reference to SL28 is, I suspect, a reference to a cultivar (or more likely a specific clone) and this is also the case with tea. And, just as any coffee, theoretically, can be washed or not and roasted to different level, any tea cultivar can produce any type of tea - and often is. However, certain teas are judged to be preferable when made with certain specific cultivars.
@teaformeplease is absolutely correct: until rather recently, specific cultivars were rarely, if ever, mentioned by vendors (although that is slowly changing) so their influence was not widely known. As someone who claims expertise with Taiwanese oolongs, I do know what to expect from a Lishan
qing xin wulong with low oxidation and no roasting (or at least, I pretend I do) but I haven't a clue what "washed SL28 roasted to the second crack" would, or should, taste like. After tasting a lot of coffee (but sorry, I don't drink coffee), however, I suspect I could learn to recognise what the influence of different cultivars is. In tea, there are so many different cultivars that no one ever can claim to be an expert in all of them. I think that what
@Bok was suggesting is: drink a lot of tea and ask questions about cultivar from the vendor (or grower). You'll start to see patterns develop and you'll learn how roast and oxidation levels affect these patterns.
I don't know if this helps or harms but should you have more questions please ask them. I, for one, amy happy to
try to help.
I use them quite a bit for explaining differences in coffee. It’s quite amazing how vastly different each tea can be all from one single plant depending on those variables. I tried a pu-erh yesterday for the first time and it was very earthy, smooth and clean tasting. It might sound odd but the earthiness reminded me of a fresh flowing creek with mineral rich soils reminiscent of when I was a kid playing and searching for salamanders. I look forward to trying more and comparing the differences. Once again, down the rabbit hole into a world of new discoveries and I can’t wait to experience them all. 
