If you had originally said most strains can PARTIALLY be traced back. As in theyre decended from crosses made with the old strains, Id agree. You however stated that they're simply phenotypes of those old strains.
Different phynotypic expressions of Jack Herrer are still Jack Herrer, they simply show different expressions of their parents. Simply renaming it wouldn't make it a new strain in anything other than name. The parental lineage is the same. The variences come from some expressing more of the mother or fathers traits.
Wheather i mentioned it or not it is a moot point, what i said is true, that many times a standout
Now if you took that same Jack Herrer pheno and crossed to another strain then yes, you can trace it back to being partially Jack Herrer. But it is no longer Jack Herrer and you cannot simply say that its just a phenotype of Jack Herrer
See my point?
Except you didnt mention crosses in the post I replied to. You simply said todays strains are phenotypes of all the old strains