It is more complicated than just THC% numbers as not like alcohol where 151 will mess you up faster than 80 proof, so Cannabis more "complicated" than that as a variety of chemicals in the makeup. Throw in everyone's body can be different chemically and one that may do a number on me might just be so-so to someone else (I grew a Panama Red that was supposed to have some CBD in it's makeup, it had an old school creeper effect on me but my Son didn't care for it as he had to smoke twice as much as his normal to get "high" he wanted). As have bought stuff with much lower number at Dispensary that kicks as hard or harder than ones higher personally, along with tests vary as numbers on one part of the plant will be different than others. So I shop more with my eyes and nose personally, but probably the "majority" out there use the % numbers to shop by and the Budtenders at Dispensaries will cater to that or they even feel it is major criteria too like the masses.
Example: Told lady at Dispensary I wanted something to knock me out so I could get some sleep (shut my brain off as "Life is such, such is Life" right now for me) NBK OG (Natural Born Killer according to websearch):
Do I think it really 40%? Many of folks in thread I posted in have doubts on that one too, as you can only get so high of accurate numbers w/o boosting it up with oils or kief or whatnot like "moonrocks" in example. But it does have a nice kick to it and filled purpose I wanted it for but so was a Grand Daddy Purple I also have for a nighttime Indica that is 21.4% according to lable/lab test (I like variety and if I smoke same Strain for days in a row it doesn't affect me the same by the end of the week).
Back on track sorry for the train derailment
....there are so many good Strains out there along with all the variables involved, as 5 different people could all grow some seeds from the same batch of a specific Strain and get 7 different results (well ok 5 but you get my drift
). Throw in other variables like so many different phenotypes in the Poly-Hybrids of today the same "Strain" can have a variety of who it takes after in it's lineage just like kids from the same two parents don't come out the same in humans and some traits are more dominate and others that are recessive can show up at times. So by your example a Strain you grew in 2001 could be totally different (or more similar) as doubtful the seeds came from the same two parents, same as you can buy "Strain X" at multiple places from multiple different growers and have totally different stuff. And then throw in the "I remember when....." factor (which is first sign of getting older when you start saying that
) to complicate things. So genetics is important as you can't easily get "killer" from crap except for the occasional genetic throwback, but if your other variables are way off or different like your light type/nurients/grow medium/etc.....it is quite easy to get crap from killer genetics. Personally I like old school landrace strains, but of the modern Hybrids/Polyhybrids I seem to like most with Blueberry or Durban or Granddaddy in it's make up somewhere, but that could be a taste thing same as some folks don't like a certain "flavor" and others think it is the bomb.
Looks like ya got it dialed in nice on the fertilizer as well... gonna have to look through your journals now lol.
...and I use Fox Farms Ocean Forest soil with Mega Crop, and you're more than welcome to take a walk through my garden anytime 
And that's why I always do a pheno hunt with at least 3 seeds from the same batch, sometimes I have to order more beans to get the pheno I want.
I had no idea they weren't a sponsor anymore, but 
