There's an argument that age of the plant is carried along in the genetic protein strand. This argument is supported in the fact that you can start budding clones earlier than similiarly-sized seedlings.

A plant is much more simple genetically than say, a lizard, puppy, or human, so throwing off chromosomes with mutations being just as likely as with other species, it's less tolerable to plants because of their simple genetic structure, and larger relational impact on the total chromosome.

Regardless of the complexity of the genetic structure, there is an inital marked increase in vigor with clones taken off seeded plants vs. that from recursive clones (clones of clones of clones, etc.), and this diminishing-vigor effect becomes more noticable over time (sometime years, depending on strain).

These "much sought after strains", if authentic, can be rather difficult to re-propogate, unless a seeded chromosome is thrown into the mix on occasion.

Simple Mendelian Genetics should be a prerequisite for all growers who don't have instant,verifiable,reliable access to quantity of seeds of known strain.