Hi Elmer
That's a razor-sharp observation you made there and imho, quite correct.
As Nevil said, the main reason why Sk1 was used a lot in breeds was the way it improved the floral structure of plants.
What I mean is, skunk always passes on some desirable floral traits - excellent calyx-to-leaf ratio, prolific production of budmass etc. In short, you had a plant that was great smoke but didn't grow big, chunky buds with not much leaf, the best way to improve it in those regards was cross it to a Skunk.
Nevil also used the NL5 cutting in a similar way when he crossed the Haze to it, the NL5 shortened the flower time, increased the size, density and resin coverage of the flowers etc, basically, the NL5 contributed a lot of desirable growth qualities but being a somewhat netral smelling/tasting plant, the Haze smell/taste totally dominated in the hybrid.
As we all know by now, Nevil's downfall as the breeder came at the beginning of the 90s and within a couple of years of Nev's legal battles it wasn't possible to easily obtain skunk and nl of top quality to breed with. C99's lineage is well known but I'll state it again for clarity:
Mr Soul had three plants he grew from seeds he found in a bag of Jack Herer bought in the Sensi shop in 95. He called these three females Genius, Cafe Girl and Princess. Princess is the one he used to make C99.
The inital f1 cross was Princess to a ShivaSkunk male, ShivaSkunk being Sensi's rename of Nevil's NL5 x Skunk.
Mr Soul then did three filial backcrosses, each time taking the most Princess dominant male and crossing it back to Princess herself. He called this process 'cubing'.
Anyways, the result of this was C99, a 56-day very chunky, good yielding and resinous strain that bred true for those desirable traits. Many loved it's high as it had a somewhat sativa high but in an 8 week plant, many also loved it's taste which was very fruity and in the best pheno, like pineapples.
C99 became like Skunk - used to add desirable growth/floral traits to other plants, usually by using a C99 male, same as Nevil used a Skunk male.
Hence there are so many strains these days with C99 in them, same as 15 years ago so many strains had Skunk1 in them.
This is C99 grown in 2004 from f2s of the original Bross Grimm C99 release.
Nevil has said that the batch of 'Jack Herer' that the seeds Mr Soul started with came from was a very NL5 dom batch. I think that C99 represents an inbred line that is mostly NL5 traits with some Skunk influence (the size of the buds and the calyx-leaf ratio) and some Haze influence clear from the nature of the high it has.
But it's mostly NL genes and it really shows. If Nev still had the NL5 cut and wanted to re-do the tragically lost work he did where he linebred and backcrossed for 8-9 gens to create an NL5 IBL, he couldn't do better than begin with a C99 male imho.
P.S. Sorry I didn't trawl back through Nev's posts to find the quotes about the JH batch the C99 came from and the info on skunk's breeding qualities and how NL5 bred well due to it's somewhat neutral palette. It's all there if people do want to go check though, Elmer can probably ask Nev about it in person sometime anyways, they are both in Oz after all...